US3201499A

US3201499A - Method and machine for producing a web of textile fibres held together by a binder

Info

Publication number: US3201499A
Application number: US145607A
Authority: US
Inventors: Casse Marcel
Original assignee: Individual
Current assignee: Individual
Priority date: 1960-12-07
Filing date: 1961-10-17
Publication date: 1965-08-17
Anticipated expiration: 1982-08-17
Also published as: GB922502A; FR1282103A

Description

Aug. 17, 1965 M. cAss 3,201,499

METHOD AND MACHINE FOR PRODUCING A WEB OF TEXTILE FIBRES HELD TOGETHER BY A BINDER 3 Sheets-Sheet 1 Filed Oct. 17, 1961 3,201,499 METHOD AND MACHINE FOR PRODUCING A WEB OF TEXTILE FIBRES Aug. 17, 1965 M. cAss HELD TOGETHER BY A BINDER 3 Sheets-Sheet 2 Filed Oct. 17. 1961 Aug. 17, 1965 M. cAssl-f METHOD AND MACHINE FOR PRODUCING A WEB OF TEXTILE FIBRES HELD TOGETHER BY A BINDER 3 Sheets-Sheet 3 Filed Oct. 17. 1961 United States Patent METHUD AND MACHINE FGR PRODUCING A WEB OF TEXTILE FIBRES HELD TUGETHER BY A BINDER Marcel Cass, 69 Rue Feray, Corbeil Essonnes, France Filed Get. 17, 1961, Ser. No. 145,667 Claims priority, application France, Dec. 7, 1960, 846,24fi, Patent 1,282,163 15 Claims. (Cl. 264-121) The present invention relates to the production of sheets or webs of textile fibres held together by a binder.

Various methods and apparatus are already known for producing such webs of natural or synthetic textile fibres, which latter are of the same or mixed type.

The known apparatus comprise a plurality of separate machines disposed in series relation to one another. In a first machine, (machine producing a layer of fibres) the fibres are open and dispersed in a current of air and drawn onto the perforated wall of a rotary drum or on a woven metal sheet.

In a second machine they are agglomerated by a binder. The latter is usually in solution in a liquid. This solution is generally distributed over the Web disposed in the flat position, by pulverization spraying or dipping. The web is thereafter drained or dried, it need be by application of pressure or suction so as to remove the excess solution. The liquid binder instead of being spread in a uniform manner over the web can also be deposited or injected into the web at separate points, in lines or in any other manner, which leaves portions of the web devoid of binder and renders the web more supple and more permeable to air.

Sometimes, a binder in powder form, which is a. thermoplastic product, is mixed with the fibre at the moment of formation of the web.

The two types of binder, namely the solution and the powder, are sometimes combined.

In a third machine, the web supported in the fiat condition by a belt or sheet material which is usually metallic, passes into an oven where it is dried and where the binder is, if required, melted if it is a thermoplastic powder or polymerized if it is a synthetic resin.

In these known apparatus, the machines disposed in series relation to one another are interconnected by suitable devices, such as belts or other conveyors.

The assembly is costly and space-consuming, and serious difficulties are encountered as concerns advancing the web and synchronization between the various machines.

The object of the present invention is to provide an improved method of producing a web of textile fibres held together by a binder which avoids the aforementioned disadvantages. This method comprises slowly and continuously rotating a single perforated cylindrical wall of large diameter and continuously forming on said wall the web of fibres, agglomerating the latter by means of the binder and drying the web on said wall and finally removing this dried web from said wall.

This method avoids all the problems of advancing or feeding the web and synchronization.

Another object of the invention is to provide a machine for carrying. out said method. This machine comprises I in combination: a perforated cylindrical wall, means for driving the wall in rotation about its geometric axis which 'is stationary, and various fixed stations arranged about said axis in such manner as to be traversed successively in a fluid-tight manner and continuously by the various portions of said wall in the course of its rotation, said stations comprising at least one station for depositing fibres in the form of a web on said wall, a station for depositing a binder on said web, a station for heating the Patented Aug. 17, 1965 web which has received the binder and a station for separating the dried web from said wall.

Further features and advantages of the invention will be apparent from the ensuing description, with reference to the accompanying drawings to which the invention is in no way limited.

In the drawings:

FIG. 1 is a longitudinal vertical sectional view, with parts cut away, of a machine according to the invention, this view being taken along line 1-1 of FIG. 2;

FIG. 2 is a sectional view taken along line 2-2 of FIG. 1;

FIG. 3 is a plan View of the machine;

FIG. 4 is a partial view of a modification of the web forming station which produces a sandwich type web;

FIG. 5 is a partial sectional view of another modification of said web forming station, and

FIG. 6 is a plan view, partly in section, of the station shown in FIG. 5.

In the embodiment shown in FIGS. 1-3, fixed on a stand 1 (FIG. 2), is a column 2, carrying at its upper part a fixed case 3. Iournalled in the latter on two bearings 4 is a horizontal shaft 5 having an axis XX. This shaft is rotated in the direction of arrow (FIGS. 1 and 2) by an electric motor 6 through belt means 7, a speed variator 8, a transmission having a sprocket 9, a chain 10 and a sprocket 11 and through a gear train having a worm 12 rigid with the sprocket 11 and a worm wheel 13 keyed on the shaft 5.

The shaft 5 extends out of the case 3 and carries keyed thereon a circular large diameter disc 14 (FIG. 2). Fixed to the periphery of this disc is a ring 15 on which is fixed a cylindrical wall 16 constituted by a perforated sheet. A second ring 17 is fixed at the other end of the cylindrical wall 16 and renders the latter rigid.

The rotary drum T constituted by the disc 14, the perforat ion wall 16 and the

rings

15 and 17, is located within a large housing or casing C whose main function will be explained hereinafter and which consists of (FIGS. 1 and 2) base 18, disposed within the stand 1 and having front and

rear traverse walls

19 and 20 respectively in which are provided apertures 21 and 22 concentric with the axis XX and having a diameter slightly greater than the cylindrical wall 16,

side walls

23 and 24 and a partial top Wall 25. Fluid tightness between the drum T and the walls 19 and 21) is obtained by means of two elastically yieldable sealing rings 26 and 27 of rubber or like material.

The drum T having a perforated cylindrical surface 16 furthermore rests by its ring 17 on two rollers 28 which are freely rotative on their spindles 29 carried by the casing C, for example directly bythe rear wall 20.

The rotary drum T is closed at the end thereof remote from the disc '14 by a fixed disc 30 located with slight clearance in the ring 17 and fixed to the sealing ring 27.

The drum T which rotates in the direction of arrow f with the shaft 5 with which it is rigid, co-operates with five fixed stations which are arranged about the axis XX and are continuously traversed by the wall 16 in the course of rotation of the drum.

The stations are:

A stationl for depositing a web 11 (FIG. 1) of fibres on the cylindrical wall 16.

A station II for providing-this web with a liquid containing a binder so as to obtain an agglomerated web n Astation III for drying the web and, if required, melting or polymerizing the binder so as to provide an agglomerated web n A station IV for removing the completed Web N from the drum T. Y

A- station V for cleaning and preparing the perforated wall 16 of the drum T.

The station I comprises two associated casings A and A located respectively outside and inside the drum T. At the upper part of the casing A arrives a current of air denoted by the arrows F. This current of air is tranquillized and downwardly directed by a grid 31.

The outer casing A is open at its base and a seal is provided between the wall 16 and this casing by a roll 32 which is capable of rolling and freely moving vertically in a slideway or guide 33. A rubber strip 34 fixed to the wall 35 of the guide lightly bears against the roll 32.

The casing A disposed within the perforated wall 16 has an upper opening corresponding to the lower opening of the outer casing A Sealing strips 36 of synthetic rubber or like material are fixed along the edges of this upper opening.

The inner casing A is fixed to the fixed disc 30 and it comprises a rear opening '37 which puts it in communication with the inlet of a fan 39 by way of a duct 38, this fan being driven by a motor 40 (FIG. 3). The air discharged by the fan 39 is directed by a duct 41 to the upper part of the casing A above the grid 31.

The station I is completed by means for feeding and dispersing fibres in the casing A below the grid 31. These means comprise:

A lower feed device G (FIG. 1) formed of an endless belt 4-2 on which the fibres are deposited at F either manually or by means of a known device (not shown) such as a loading or combined loading and weighing device, two feed rolls 43 which feed the fibres toward a picker 44 (cylinder provided with spikes or pins) and a duct 45 for raising the fibres F dispersed by the picker.

An upper receiving device H, for receiving the fibres F and for dispersing the latter at F in the current of air emanating from the grid 31, comprises a rotary perforated cylinder 48 which is located within a lateral housing 46 formed in the wall 47 of the casing A and which receives the fibres, two feed rolls 48a against which the perforated cylinder 48 lightly rubs, a picker 49, and a rotary brush 50 carrying longitudinal bars 51.

The various rolls and cylinders, the pickers and the brush are driven in rotation in the directions indicated by the arrows in FIG. 1 through conventional transmission means (not shown) by

electric motors

52 and 53 respectively.

The station II for spraying an agglomerating liquid on the layer of fibres deposited on the drum is located immediately after the station I relative to the direction of rotation of the drum T. It comprises two associated casings, namely a casing B outside the wall 16 and a casing B within this wall.

The outer casing B is carried by the wall 25 and fluid tightness between the casing B and the cylindrical wall 16 is obtained by means of a rubber strip 34 which bears against the roll 32 and by means of a plate 54 the height of which is adjustable.

The inner casing B is carried by the disc 30 and fluidtightness is obtained therebetween and the wall 16 by means of two

rubber strips

55 and 56.

The outer casing B contains a spraying jet 57 whose lower wall is perforated with small-diameter orifices 58. This jet 57 is nearer to the wall 35 of the casing B than to the wall 59.

The inner casing B is connected to a duct 60 which puts the inside of this casing in communication with the inlet of a fan 61 which is capable of maintaining a high degree of vacuum or negative pressure in this casing, is driven by the motor 62 and discharges into the atmosphere at 63.

The lower wall 64 of the casing B is inclined and leads to a hydraulic seal 65 (FIG. 2) whose overflow liquid flows by way of a pipe 66 into a tank 67 covered by a wire netting 68. A pump 69 draws the water or the appropriate solution from this tank67 and pumps it into the jet 57 by way of a pipe 70 provided with a regulating cock 71.

. It is said that certain fibers swell.

The heating station III is disposed in and around the large casing C. An opening 72 (FIG. 1) formed in the disc 3% puts the interior of the perforated cylindrical wall 16 in communication with the inlet of a fan 74 FIG. 3) by way of a duct 73 (FIG. 2). This fan, which is driven by a motor 75, discharges the air drawn in through the opening 72 into an air heater 76. In the presently described embodiment, this air heater comprises a vertical case 77 at the lower part of which is located a combustion chamber 78 into which extends a burner 79. The gases of the combustion rise vertically in the tubes of a nest of tubes 80 and are evacuated by way of a chimney 81. The air discharged by the fan 74 passes around the tubes 80 and is returned to the casing C by way of a duct 82.

The hot gases arrive in the part or casing C formed in the housing C about the drum T, pass through the web n and the perforated wall 16 and issue from the interior C of the drum by way of the opening 72.

The station IV adapted to separate the formed web N from the wall 16, comprises (FIG. 1) a strip or doctor 83 which rubs against the outer face of the wall 16 and two

rolls

84 and 85, the roll 85 being as close as possible to this perforated wall 16.

These rolls 84 and 85 are operatively interconnected as concerns rotational movement, owing to provision of a pair of gears 86 (P16. 3), and are driven by a pair of bevel gears 87 which are driven by the shaft of the worm 12 by way of a shaft 88. The gear ratio of the bevel gears 87 is so arranged that the peripheral speed of the

rolls

84 and 85 is identical to that of the perforated wall 16.

At the station V for cleaning and preparing the perforated cylindrical wall 16, a case B inside the wall 16 contains one or more perforated tubes 89 which are parallel to the axis of the cylindrical wall 16 and are capable of being connected to a source of compressed air or steam (not shown). Disposed outside the wall 16 in alignment with the case E and with a perforated tube 89, is a rotary brush 90 surrounded by a hood E which is connected by way of a pipe 91 to a fan (not shown). A strip of felt 92 impregnated with an oily substance or with a product providing an insulating film, for example a varnish having a silicone base, rubs against the outer face of the wall 16 before the latter passes under the casing A The machine operates in the following manner:

At the station I, on the portion ab (renewed in a continuous and uninterrupted manner) of the wall 16 there is formed the fibre web 12 the fibres, divided and dispersed at F by the picker 49 and the brush 50 in the casing A being carried by the current of air issuing from the grid 31 and distributed uniformly over said portion ab. This portion tab constitutes in fact a perforated bottom for the casing A The air is received in the associated inner casing A and discharged toward the grid 31; this air therefore travels in a closed path across which extends the perforated wall 16.

The web n thus formed reaches in a continuous manner the station II where the jet 57, supplied by the pump 69 with hot or cold liquid containing a binder in solution or emulsion, atomizes this liquid and distributes it in the form of a spray over the entire portion cd of the portion n of the fibre web. The high degree of suction maintained within the associated inner casing B by the fan 61 achieves a perfect penetration of the binder in the web n and a drainage of excess liquid.

Experience has shown that the abundant spraying of the portion n. of the fibre web combined with an energetic suction highly compresses or achieves a packing of the fibres of the web and interconnects the fibers.

If it is desired to obtain a web of high density, the layer n of fibers has a thickness of several centimeters. The compressing of the middle layer.

of this thick layer by the rolls would create sliding,

wrinkles, and irregularities in the thickness. On the other hand, the abundant spraying at n of this thick layer subjected to a high suction brings about a very large decrease in the thickness of the fibers and the thickness of the layer could be reduced from, for example, ten centimetres to one centimetre.

The part of the perforated wall 16 carrying the portion of the'web impregnated at n thereafter passes by the Station III in which the air (or other hot gases) passes in the direction from C to C This hot air, after having passed through the Web at 11 is drawn in by the fan 74 which blows it into the generator 76 generating hot air or other gas and returns it to the outer casing C At the exit end of the station III the web it is separated at IV from the wall 16 by the strip 33 and is gripped between the two rolls 84- and 85. The separated web N can thereafter pass between other rolls (not shown) which could be, if required, cooled; these other rolls grip it and impart thereto a uniform thickness. The web is thereafter either rolled up, cut to the required length, or fed to other devices effecting further operations.

The last station V permits cleaning the perforated wall 16, this cleaning being carried out, for example, by jets of compressed air or steam issuing from the perforated tubes 89. To'the same end, the (or several) rotary brushes 9% act on the outer face of the wall 16.

The felt strip 92 (or a brush) deposits on the perforated wall 16 a film of oil, grease, wax or suitable varnish adapted to prevent the binder used for agglomerating the fibers of the web from causing the latter to adhere to the wall 16.

It will be observed that the air drawn into the lower casing B can be recycled if required in the upper casing B so as to return to the web the fibers or products, such as binding powders, granulated cork or active charcoal which could be incorporated in the web.

Infrared radiators could be disposed in the casing C so as to direct a heating flux toward theweb n At the station IV the web N could be separated from the wall 16 bymeans other than the strip 83, for example by jets of air or other compressed gas.

It might be required that the web be composed of two or several superimposed layers, for example so as .to constitute a sandwich type web in which the middle layer of fibers which are cheap or of a mixture offibres and various added products (such as granulated cork, wood cuttings, active charcoal) is placed between two layers of fibres of superior quality having for example greater strength or a better appearance than the fibres In this case the single outer casing A of the example described hereinbefore is replaced by as many elementary casings as there are layers of fibres to be superimposed, these elementary casings being disposed one after the other along the perforated wall 16 and constituted, for example, by a simple subdivision of the casing A Each elementary casing receives, dispersed in a current of air, the desired fibres which are, if

.A is subdivided by a partition wall 93 into two

elementary casings

94, 95 each of which receives fibres and the air which entrains these fibers through a duct 96 or 97, the fibres being distributed in the lower part of the corresponding duct, for example by a picker 98, whereas the primary air under pressure is injected through a nozzle 99 so as to entrain the fibres in'a stream 'of air formed of this primary air and secondary air entering at 100'.

FIGS. 5 and 6 show a modification of the device adapted to forma composite web comprising two outer-layers p and q of fibres and therebetween a layer r constituted by a granulated or powdered product, such as cork or active charcoal.

- A tank or hopper 101 contains at 102 the powdered or granulated product which falls into the apertures 103 of a disc 16-:- rotating between two side members 105 and 1%. The upper member 1135 has an opening 107 in alignment with the base of the hopper 101. The lower member 1% has an opening 198 which is diametrally opposed to the opening 107 of the hopper member. The disc 164 is driven at adjustable speed by a motor 109 through a speed variator 11%). Under the opening 108 of the lower member 106 there is located a hopper 111 communicating with the inlet of a fan 112 driven by a motor 113. The assembly just described constitutes a dosing or metering device.

The air arriving in the hopper 111 can be taken from the discharge pipe of the fan 39 (FIG. 3).

The discharge side of the fan 112 is equally divided into two

nozzles

114, 115 which communicate with a chamber 116 through the side walls of the latter, this chamber being arranged under a hood 117 disposed in the casing A This hood 117 has an ogival vertical sectional shape (FIG. 5) and no bottom. The outlets of the two

nozzles

114 and 115 are offset in plane and in elevation in the chamber 116. Y

Although specific embodiments of the invention have been described, many modifications and changes may be made therein without departing from the scope of the invention as defined in the appended claims.

Having now described my invention what I claim as new and desire to secure by Letter Patent is:

1. Method of producing a web of fibres held together by a binder consisting of the steps of depositing at a first station directly on a rotating perforated cylindrical wall, loose fibres carried along in a stream of air directed through the perforated wall, spraying at a'second station .following the first station, relative to the direction of rotationof the perforated wall, a liquid binder directly onto the layer of fibres deposited on the perforated wall while creating a high suction on the side of the wall opposed to said layer in the region of the layer receiving the sprayed liquid binder so as to achieve substantial penetra- .a web of fibres bound together by a binder.

2. Method of producing a web of fibers held together by a binder consisting of the steps of depositing at a first station directly on a rotating perforated cylindrical wall, loose fibres carried along in a stream of air directed through the perforated wall, spraying at a second station following the first station, relative to the direction of rotation of the perforated wall, a liquid binder directly onto the layer of fibres deposited on the perforated wall while creating a highsuction on the side of the wall opposed to said layer in the region of the layer receiving the sprayed liquid binder so as to achieve substantial penetration of the liquid binder into the layer and a compression of the layer, drying the layer in a third station .following the second station, relative to said direction of rotation 'by forcing a hot gaseous fluid directly onto the layer and through the latter and into the perforated wall,

removing, at a fourth station following the third station, .the dried layer from the perforated wall in the form of a web of fibres bound together by a binder, and, at a fifth station following the fourth station, cleaning the perforated wall and applying on the fibre-receiving face there- 4. A method as claimed in claim 2, wherein said product is an oily substance.

layer, the step of radially compressing the layer consisting of creating a high suction on the side of the perforated wall opposed to the layer in the region of the layer receiving the liquid binder.

6. A machine for producing a web having bonded fibres, comprising in combination: a stand, a perforated cylindrical wall rotatably mounted on the stand, driving means operatively connected to the wall for rotating the wall about the axis thereof so that the wall moves through a circular path, first means for depositing a web of fibres on the perforated wall in a first segment of said path, second means for depositing a liquid binder on said web on the wall in a second segment of said path, third means for blowing hot gases through the web of fibres on the wall in a third segment of said path and fourth means for detaching the web from the wall, the first, second, third and fourth means being arranged about said axis in succession in the order stated relative to the direction of rotation of the wall, said first means and third means each comprising an outer casing located outside the perforated wall and an inner casing located inside the perforated wall, the perforated wall being common to the inner and outer casings and sealing means being interposed between the inner casings and the perforated wall so that the inner casings respectively communicate only with the corresponding outer casings through the perforations of the perforated wall, gas suction means connected to the inner casings of the first means and third means, gas blowing means connected to the outer casings of the first and third means, whereby a current of gas is created within the casings of the first means and third means, heating means inserted between the gas blowing means and the perforated wall of the third means for heating the gas passing through the perforated wall in said third segment of the path and thus drying the web of fibres.

7. A machine for producing a web having bonded fibres, comprising in combination: a stand, a perforated cylindrical wall rotatably mounted on the stand, driving means operatively connected to the wall for rotating the wall about the axis thereof so that the Wall moves through for blowing hot gases through the web of fibres on the wall in a third segment of said path and fourth means for detaching the web from the wall, the first, second, third and fourth means being arranged about said axis in succession in the order stated relative to the direction of rotation of the wall, said first means and third means each comprising an outer casing located outside the perforated wall and an inner casing located inside the perforated wall, the perforated wall being common to the inner and outer casings and sealing means being interposed between the inner casings and the perforated wall so that the inner casings respectively communicate only with the corresponding outer casings through the perforations of the perforated wall, gas suction means connected to the inner casings of the first means and third means, gas blowing means connected to the outer casings of the first and third means, whereby a current of gas is created within the casings of the first means and third means, heating means inserted between the gas blowing means and the perforated wall of the third means for heating the gas by the effect of the suction created in the inner casing of the first means.

8. A machine for producing a web having bonded fibres, comprising in combination: a stand, a perforated cylindrical wall rotatably mounted on the stand, driving means operatively connected to the wall for rotating the wall about the axis thereof so that the wall moves through a circular path, first means for depositing a web of fibres on the perforated wall in a first segment of said path, second means for depositing a liquid binder on said web on the wall in a second segment of said path, third means for blowing hot gases through the web of fibres on the wall in a third segment of said path and fourth means for detaching the web from the wall, the first, second, third and fourth means being arranged about said axis in succession in the order stated relative to the direction of rotation of the wall, said first means and third means each comprising an outer casing located outside the perforated wall and an inner casing located inside the perforated wall, the second means having an inner casing located inside the perforated wall, the perforated wall being common to the inner and outer casings and sealing means being interposed between the inner casings and the perforated wall so that the inner casings respectively communicate only with the corresponding outer casings :through the perforations of the perforated wall, gas suction means connected to the inner casings of the first anean, second means and third means, gas blowing means connected to the outer casings of the first and third means, whereby a current of gas is created within the casings of the first means and third means, and a suction is created in the inner casing of the second means, heating means inserted between the gas blowing means and the perforrated wall of the third means for heating the gas passing 'through the perforated wall in said third segment of the path and thus drying the web of fibres, the first means comprising a device for throwing fibres into the current of gas in the corresponding outer casing whereby the fibres are deposited on the perforated wall by the etfect of the suction created in the inner casing of the first means, the second means comprising a spray pipe located outside the perforated wall for spraying a liquid binder onto the web of fibres.

9. A machine as claimed in claim 6, wherein the third segment of said path corresponds to the major part of said perforated wall.

10. A machine for producing a web having bonded fibres, comprising in combination: a stand, a perforated cylindrical wall rotatably mounted on the stand, driving means operatively connected to the wall for rotating the wall about the axis thereof so that the wall moves through a circular path, first means for depositing a web of fibres on the perforated wall in a first segment of said path, secand means for depositing a liquid binder on said web on the wall in the second segment of said path, third means for blowing hot gases through the web of fibres on the wall in a third segment of said path and fourth means for detaching the web from the wall, the first, second, third and fourth means being arranged about said axis in succession in the order stated relative to the direction of rotation of the wall, said first means and third means each comprising an outer casing located outside the perforated wall and an inner casing located inside the perforated Wall, the second means having an inner casing located inside the perforated wall, the perforated wall being common to the inner and outer casing and sealing means being interposed between the inner casings and the perforated wall so that the inner casings respectively communicate only with the corresponding outer casings through the perforations of the perforated wall, gas suction means connected to the inner casings of the first means, second means and third means, gas blowing means connected to the outer casings of the first and third means, whereby a current of gas is created within the casings of the first means and third means, and a suction is created in the inner casing of the second means, heating means inserted between the gas blowing means and the perforated wall of the third means for heating the gas passing through the perforated wall in said third segment of the path and thus drying the web of fibres, the first means comprising a device for throwing fibres into the current of ,gas in the corresponding outer casing whereby the fibres are deposited on the perforated wall by the effect of the suction created in the inner casing of the first means, the second means com prising a spray pipe located outside the perforated wall for spraying a liquid onto the web of fibres, the machine further comprising a fifth means interposed between the first and fourth means for cleaning the outer face of the perforated wall.

11. A machine as claimed in claim 10, wherein the fifth means comprises a rotary brush applied against the outer face of the perforated wall, and an inner casing which is located inside the perforated wall and is in fluid tight engagement with the latter, a perforated tube connected to a source of gas under pressure being disposed within the inner casing of the fifth means for blowing gas through the perforated wall.

12. A machine as claimed in claim 11 wherein the fifth means further comprises a strip of soft porous material impregnated with a liquid product and applied against the outer face of the perforated wall between the rotary brush and the first means, said liquid product being such that a coating thereof on the perforated wall insures that the fibres deposited on the perforated wall by the first means do not adhere to the outer face of the perforated wall.

13. A machine for producing a web having bonded fibres, comprising in combination: a stand, a perforated cylindrical wall rotatably mounted on the stand, driving means operatively connected to the wall for rotating the wall about the axis thereof so that the wall moves through a circular path, first means for depositing a web of fibres on the perforated Wall in a first segment of said path, second means for depositing a liquid binder on said web on the wall in a second segment of said path, third means for blowing hot gases through the Web of fibres on the wall in a third segment of said path and fourth means for detaching the web from the wall, the first, second, third and fourth means being arranged about said axis in succession in the order stated relative to the direction of rotation of the wall, said first means and third means each comprising an outer casing located outside the perforated wall and an inner casing located inside the perforated wall, the perforated wall being common to the inner and outer casings and sealing means being interposed between the inner casings and the perforated wall so that the inner casings respectively communicate only with the corre-' sponding outer casings through the perforations of the perforated wall, gas suction means connected to the inner casings of the first means and third means, gas blowing means connected to the outer casings of the first and third means, whereby a current of gas is created within the casings of the first means and third means, heating means inserted between the gas blowing means and the perforated wall of the third means for heating the gas passing through the perforated wall in said third segment of the path and thus drying the web of fibres, the first means comprising means dividing the outer casing thereof into a plurality of passages respectively communicating with the gas blowing means and the perforated wall in circumferentially adjacent regions of said first segment of said path, and a plurality of supply devices respectively associated with said passages for respectively supplying different types of constituent substances for making up a multiply web including fibres.

14. A machine for producing a web having bonded fibres, comprising in combination: a stand, a perforated cylindrical wall rotatably mounted on the stand, driving means operatively connected to the wall through a speed variator for rotating the wall about the axis thereof so that the wall moves through a circular path, first means for depositing a web of fibres on the perforated wall in a first segment of said path, second means for depositing a liquid binder on said web on the wall in a second segment of said path, third means for blowing hot gases through the web of fibres on the wall in a third segment of said path and fourth means for detaching the web from the wall, the first, second, third and fourth means being arranged about said axis in succession in the order stated relative to the direction of rotation of the wall, said first means and third means each comprising an outer casing located outside the perforated wall and an inner casing located inside the perforated wall, the perforated wall being common to the inner and outer casings and sealing means being interposed between the inner casings and the perforated wall so that the inner casings respectively communicate only with the corresponding outer casings through the perforations of the perforated wall, gas suction means connected to the inner casings of the first means and third means, gas blowing means connected to the outer casings of the first and third means, whereby a current of gas is created within the casings of the first means and third means, heating means inserted between the gas blowing means and the perforated wall of the third means for heating the gas passing through the perforated wall in said third segment of the path and thus drying the web of fibres, the outer casing of the first means having a casing wall structure under which the deposited fibres pass to reach the second means, said casing wall structure being yieldably biased toward the perforated wall so as to accommodate variations in the thickness of the deposited web due to variations in the speed of rotation of the perforated wall obtained by means of said speed variator.

15. A machine for producing a web of fibres, consisting of a stand, a perforated cylindrical wall having a substantially horizontal axis and 'rotatably mounted on the stand, driving means operatively connected to the perforated Wall for driving the latter through a circular path about said axis, first means including a suction chamber inside the wall and loose fibre distributing means outside the wall for depositing the loose fibres on the perforated wall in the form of a web by the effect of said suction chamber, second means including an inr ner casing fixed relative to the stand and located inside and in fiuidtight contact with the wall and a liquid supply spraying pipe located outside the wall in spaced relation to the wall for spraying liquid onto said web, the inner casing being connected to the inlet of a suction pump whereby a high vacuum is created in the casing which compresses the fibres and reduces the radial thickness of the web, athird means comprising an outer casing located outside the wall and connected to a source of hot gases under pressure and an inner casing located inside the wall and in fluidtight contact with the wall and con nected to a suction pump, the perforated wall being common to the inner and outer casings of the third means, whereby the web of fibres is directly exposed to said hot gases which pass therethrough and into the inner casing of the third means, and fourth means adapted to be interposed between the perforated wall and the web leaving the third means so as to separate the web from the perforated wall.

References Cited by the Examiner UNITED STATES PATENTS Gengenbach 156369 (tilther references on following page) 1 2 FOREIGN PATENTS 212,006 4/ 60 Austria. 479,794 12/51 Canada. 558,783 6/58 Canada.

ALEXANDER H. BRODMERKEL, Primary Examiner.

EARL M. BERGERT, Examiner.

Claims

1. METHOD OF PRODUCING A WEB OF FIVRES HELD TOGETHER BY A BINDER CONSISTING OF THE STEPS OF DEPOSITING AT A FIRST STATION DIRECTLY ON A ROTATING PERFORATED CYLINDRICAL WALL, LOOSE FIBRES CARRIED ALONG IN A STREAM OF AIR DIRECTED THROUGH THE PERFORATED WALL, SPRAYING AT A SECOND STATION FOLLOWING THE FIRST STATION, RELATIVE TO THE DIRECTION OF ROTATION OF THE PERFORATED WALL, A LIQUID BINDER DIRECTLY ONTO THE LAYER OF FIBRES DEPOSITED ON THE PERFORATED WALL WHILE CREATING A HIGH SUCTION ON THE SIDE OF THE WALL OPPOSED TO SAID LAYER IN THE REGION OF THE LAYER RECEIVING THE SPRAYED LIQUID BINDER SO AS TO ACHIEVE SUBSTANTIAL PENETRATION OF THE LIQUID BINDER INTO THE LAYER AND A COMPRESSION OF THE LAYER, DRYING THE LAYER IN A THIRD STATION FOLLOWING THE SECOND STATION, RELATIVE TO SAID DIRECTION OF ROTATION BY FORCING A HOT GASEOUS FLUID DIRECTLY ONTO THE LAYER AND THROUGH THE LATTER AND INTO THE PERFORATED WALL, AND REMOVING, AT A FOURTH STATION FOLLOWING THE THIRD STATION, THE DRIED LAYER FROM THE PERFORATED WALL IN THE FORM OF A WEB OF FIBRES BOUND TOGETHER BY A BINDER.