US2703441A

US2703441A - Machine for forming composite fiber webs

Info

Publication number: US2703441A
Application number: US209012A
Authority: US
Inventors: Howard H Langdon; Francis M Buresh
Original assignee: Curlator Corp
Current assignee: Curlator Corp
Priority date: 1951-02-02
Filing date: 1951-02-02
Publication date: 1955-03-08
Anticipated expiration: 1972-03-08
Also published as: CH298468A; GB714283A

Description

March 8, 1955 H. H. LANGDON Erm.

MACHINE FOR FORMING COMPOSITE FIBER WEBS Filed Feb. 2, 1951 4 Sheets-Sheet l F RANG/5 M EURES/'l March 8', 1955 H. H. LANGDON :TAL 2,703,441

MACHINE FOR FORMING COMPOSITE FIBER WEBS Filed Feb. 2, 1951 4 sheets-sneer 2 IN V EN TCR3'.

HOWARD H. LANGDON BY FRANC/S M. BURESH @Wk-yf T 7' ORNEY Marh 8, 1955 H. LANGDON ErAL 2,703,441

MACHINE FOR FORMING COMPOSITE FIBER WEBS 4 Sheets-Sheet 3 Filed Feb. 2, 1951 1N V EN TORS.

A T TDRNEY March 8, 1955 H. H. LANGDON ETAL 2,703,441

MACHINE FOR FORMING COMPOSITE FIBER WEBS Filed Feb. 2, 1951 4 Sheets-Sheet 4 las Fl IN V EN TORX.

HOWARD H. LANGDON By FRA/V015 M. BUIiSHy ATTORNEY MACHINE FoRroRMrNG comosrru FIBER wEBs Howard H. Langdon, Rochester, N. Y., and Francis M.

Buresh, Blandford, Mass., assgnors, by mesne assignments, to Curlntor Corporation, Rochester, N. Y., a corporation of New York Application February z, 1951, serial No. zomerv- 16 claims. (ci. 19-156) The present invention relates to machines for forming random textile ber webs. In a more specic aspect the invention constitutes an improvement over the random web forming machine of the Buresh Patent No. 2,451,915, granted October 19, 1948and over the random web forming machine of the Buresh and Langdon pending 11. psatent application Serial No. 26,256, led May In the machines of the patent and application above mentioned the work material is fed into a lickerin, which is rotating at high speed, in such way that single bers are combed and drawn out of the material by the teeth of the rotating lickerin; the bers are dotted from the lickerin by a high velocity air stream and by the centrifugal force resulting from thehigh speed of rotation of the lickerin; and the bers are carried bythe air stream onto a rotary foraminous condenser slowly rgtating about an axis extending at right angles to the, direction of ow of the air stream. The air stream passes diametrally through the condenser; and the fibers are caught by and thus randomly deposited on the condenser. Thus a ber web is built up on the condenser which has equal strength in all directions in the plane of the web. The bers are pressed together to compact the web; and the compactedweb is delivered/.onto a conveyor or otherwise discharged from the machine.

While the machines of the patent and application above mentioned are satisfactory for webs of medium width, when the width of the web, which is to be formed, exceeds by any considerable amount 40 inches, support of the rotary condenser becomes a serious design and construction problem, because the rotary condenser or drum can only be supported at its ends since a passage through the drum has to be provided for the air stream.

In machines constructed according to the design disclosed in the patent and application above mentioned, moreover, difculty is experienced in keeping the condenser screen clean. Fibers which strike the condenser endwise are likely to pass through the perforated condenser at the side of random web formation but may be caught at the opposite side of the condenser as they at-v tempt to pass a second time through the perforations of the condenser with the air stream owing to the suction fan. lf these caught bers are not removed they gradually accumulate on the inside of the condenser; and this accumulation can become serious in continued operation of the machine because it will reduce the air ow. Sometimes, moreover, there may be a discontinuous warp wire with an end sticking out and bers will be caught by this wire and stick to the outside surface of the condenser screen.

In some instances, it may be desirable to form composite webs of two or more different materials, as, for instance, of ber and a ranular material like cork. In some cases it may also e desirable to stabilize the webs with a suitable bonding material. With the machines of the patent and application above mentioned a composite web cannot be formed. To make a composite web it is rst necessary to make the base random web in the machine and to then superirnpose on the base web the cork or other desired second material. With the machines of the patent and application above mentioned, stabilization cannot be effected during formation of the web and can be effected only by saturating the web with a stabilizing agent following removal of the web from the machine, and then pressing and drying the saturated web. Granular bonding agents, although widely available cannot be used United Statesl Patent 2,703,441 Patented Mar. 8, 1955 ice with webs manufactured on the machine of the patent or application above mentioned, except by building up laminar web's. The granular bonding agents would not satisfactorily penetrate the base web if sprinkled on top thereof. Therefore, webs made on the machines of the patent' and application above mentioned, are bonded commercially by laminating alternating relatively thin ber webs with sheets of bonding material, and then inserting the laminations in platen presses and applying heat and pressure to form hard boards.

One object of the present invention is to provide a machine for forming random ber webs which can be made to form a web of any desired width and in which the condenser, on which the webis formed, may be readily siflppoted so as to permit formation of the desired width o we Another object of the invention is to 'provide a machine for forming random ber webs in which a condenser in the form of an endless foraminous belt may be used and in which the bers may be conveyed to the belt for deposit thereon by an air stream which is passed through both the forward and return reaches of the belt.

Another object of the invention is to provide a machine of the character described for forming random ber webs in which means is provided to prevent lateral creeping of the endless condenser belt as it travels over its rollers.

A further object of the invention is to provide a machine for forming random ber webs which is so constructed that access may readily be had to the condenser for cleaning.

Another object of the invention is to provide a machine for forming random ber webs in which the condenser can be continuously cleaned both on its inside and on its outside surfaces.

A further object of the invention is to provide a machine for forming random ber webs in which stray bers which pass through the collecting surface of the condenser on which the web is formed are automatically removed from the condenser and returned to the suction side of the fan for recirculation with other bers through the machine.

Another object of the invention is to provide a machine for forming random ber webs in which stray bers, which are caught on the outside surface of the condenser, can be removed and also returned to the suction side of the fan for recirculation of these bers through the machine.

Another object of the invention is to provide a machine of the character described in which the condenser is mounted in a separate part slidable into or out of the machine for cleaning or replacement.

Another object of the invention is to provide a machine for forming random ber webs which will permit incorporation in the web, during formation, of any dry granular material such as cork, or a granular bonding agent.

Another object of the invention is to provide a machine for forming random ber webs in which the dry granular material may be sandwiched between layers of ber during formation of a ber web, so as to build up a laminated, composite web in the machine itself.

Still another object of the invention is to provide a machine for forming random ber webs in which granular bonding agents can be introduced into the web at the time the web is formed on the condenser thus insuring good distribution thicknesswise even on heavy webs.

Another object of the invention is to provide a maclrtm for forming random ber webs having means for controlling feed of a granular material into the air stream of the machine as the air stream arries the bers to the condenser so that a controlled amount of the granular material may be evenly distributed throughout the web during formation of the web.

Other objects of the invention will be apparent herethrough one of the rolls over which the belt condenser of the machine travels, taken on the line 5--5 of Fig. 4, looking in the direction of the arrows and showing particularly the means for preventing lateral creeping of the v belt;

Fig. 6 is a fragmentary longitudinal vertical section, illustrating a machine built according to a modification of the invention;

Fig. 7 is a fragmentary longitudinal section of this modified machine on an 'enlarged scale illustrating the means for introducing granular material into the air stream of this machine so that the granular material will be sandwiched between layers of fibers in the web formed by the machine;

Fig. 8 is a side elevation of a feeder for feeding granular material to the machine;

Fig. 9 is a plan view of this feeder with parts broken away; and

Fig. l is a transverse section through the feeder.

Referring now to the drawings by numerals of reference, and more particularly first to the embodiment of the invention shown in Figs. l to inclusive. and in Fics. 8. 9 and 10. 20 indicates the base or frame of the machine. This may be made of fabricated steel with suitable reinforcements and is generally rectangular in shape. Secured to the top of the frame is a lap bed or feed plate 21 which has a fiat upper horizontal surface. A feed hopper, such as disclosed in application Serial No. 26,256 above mentioned, may be mounted above this plate to feed fibrous material to the machine, or the fibrous material may be fed over the plate in the form of a lap. A nose or riser plate 22 is fastened in any suitable manner to the right hand end of the bed plate 2l. Mounted above the bed plate and very close thereto is a feed roller 24. This is iournaled at opposite ends in the nose 22 or bed plate 21 and may be adjusted toward and from the nose 22 to control the feed of the stock material to the machine so as to dispose the stock material to the lickerin 25 of the machine in such way that the teeth of the lickerin will comb and draw out of the stock individual fibers. The lickerin 25 is provided with a plurality of peripheral lickerin teeth, which may be similar to saw teeth, and is iournaled in the frame of the machine to be driven at high speeds during the operation of the machine. The feed roll 24 is also positively driven and may be driven from the lickerin shaft or direct from a drive motor (not shown). All this is known construction and may be identical with that disclosed in either the patent or application above mentioned.

As the lickerin revolves. its teeth pick fibers from the stock being fed to it by the feed roller 24 and the teeth carry these fibers around into an air duct 30 into which the lickerin proiects. The air svstem of the machine is a closed, recirculating system like that disclosed in application No. 26.256 above mentioned. Circulation is produced by a blower or fan which is mounted within the casing 31 in the base of the machine. This blower or fan is driven bv the motor 32 through a pulley 33, belt 34 and pulley 35. The last-named pulley is secured to the shaft on which the fan is mounted. The inlet side of the fan connects with a vertical portion 36 of the duct 30 that extends the full width of the frame at one end thereof. This portion of the duct is formed between the right hand end wall of the frame and the duct plate 37. The blower housing 31 is connected at its pressure side with a portion 40 of duct 30 which is suitably supported Within the frame of the machine. The duct portion 40 connects at its left hand end with a vertical duct portion 41 which extends across the full width of the frame of the machine and which is formed between the left hand end wall of the frame and a duct plate 43. The duct portion 41 is curved at its upper endand joins a portion 44 of the duct. This portion of the duct extends beneath the feed plate 2l. the nose plate 22 and the lickerin 25. This portion 44 of the duct is formed at one side of the lickerin between the feed plate 21 and a duct plate 46, and at the opposite side of the lickerin is formed between

upper plates

47 and 48 and

lower plates

49 and 50. Tt extends across substantially the full external width of the frame 20. The duct portion 44 is nar: rowed beneath the lickerin so as to provide a venturi effect. The narrow portion of the duct is formed by the upper surface 52 of the beam 53. The upper surface 52 of this beamis so shaped that the duct converges toward the lickerin on the approach or pressure side of the lickerin and diverges from the wall or cover plate 47 on the suction side of the duct. The plate 47 is itself inclined upwardly from the lickerin so that the opposed upper and

lower walls

47 and 49 of the duct recede from one another. The air duct system so far described may be identical with that disclosed in application No. 26,256 above mentioned.

Mounted within the upper horizontal reach 44 of the air duct on the suction side of the lickerin is a condenser 60 which, in the machine of the present invention, is in the form of an endless belt made of wire mesh or any suitable reticulated material. The air circulating in duct 30 passes through both the forward and return reaches of this condenser belt, the portion 44 of the air duct within these two reaches of the belt being bounded by the upper and

lower plates

55 and 56. The air duct portion 44 is curved at its right hand end to join the duct portion 36, beiusbounded along its curved juncture by the plates 57 an The condenser belt 60 is more or less diagonally inclined to the vertical, as shown; and the

plates

47 and 48 diverge from the

plates

49 and 50, respectively, so as to expose a wide area of the upper or forward reach of the condenser for laying of the web.

The streamline flow of the air through the forward and return reaches of the condenser belt 60 insures uniform random laying of the fibers on the forward reach of the belt with a minimum of turbulence and with uniform thickness of web across the width of the condenser within practical tolerances.

The fibers deposited in random fashion on the forward reach of the condenser 60 by the high velocity air stream owing through the condenser are compressed by a pressure roller which is iournaled in the frame of the machine and which may be pressed by spring members (not shown) against the web in a manner similar to the pressure roller disclosed in application No. 26,256. The pressure roller 85 may be driven by frictional engagement with the web.

The belt 60 travels over

rolls

65 and 66. Each of these rolls may be built up by welding, as at 69, a tube 70 (Fig. 5) to a pair of end plates 71 and 72 and keying the end plates to a shaft 73 passed centrally through them. Set screws 75 may be provided to lock the keys in position. Each end plate 71 and 72 is turned down to provide an inclined outside surface 76 and a peripheral surface 79, the latter being of reduced diameter as compared to the outside diameter of the major part of the roll. Either roll 65 or 66 may be the driver and may be driven in any suitable manner from a motor (not shown).

The web, which is formed in the machine, may be removed from the machine as fast as it is formed and as the condenser belt passes over upper roller 65. The belt type screen is readily supported and may readily be made in very wide widths.

To prevent lateral creeping of the condenser belt 60 on the rollers, the belt is made wider than the width of the web which it is desired to form. At each side of the condenser belt 60 there is placed a V-belt 77 whose outside length is equal to the inside length of the condenser belt. On the outside of the condenser belt and directly over the V-belt are placed strips of rubber 78 of the same width as the outside surface of the V-belts 77, and these strips of rubber 78 are vulcanized under heat and pressure through the mesh of the screen 60 to the outside surfaces of the V-belts 77, thus making the V-belts 77, screen 60 and strips 78 integral. The peripheral portions 79 of the end plates 71 and 72 of the rolls 65 vand 66 are turned down to a diameter to clear the inside surfaces 81 of the V-belts 77 so that the inside inclined side surfaces 80 of these V-belts will engage and seat only against the outside inclined surfaces 76 of these end plates, these outside surfaces 76 of the end plates being formed at the same angle as the side surfaces 80 of the V-belts. When the screen belt 60 is moved over the two

rolls

65 and 66. then, the V-belts 77 will engage the side surfaces 76 nf the end plates 7l and 72; and the filler wires of the belt 60 will be in tension and will restrain any tendency toward lateral movement of the belt 60.

Experience has shown that some fibers will get through the mesh of the forward reach of the endless condenser arcani belt 60. Such bers may be caught on thes return reach of the belt. These fibers collect on the inside of the belt as the belt travels to the lower roll 66 on the return and are carried in this way outside of the air duct. If they are not removed they will pass around the lower screen roll 66 and be again blown off of the belt as it moves again in its forwardv reach. In time, if these fibers are not removed they will accumulate on the inside of tllile belt and lower the eliciency of operation of the mac ine.

To overcome this a suction pipe 90 is mounted inside the condenser belt 60 adjacent the returnreach of that belt but outside of the air duct 30. This suction pipe has an opening as denoted at 91. It is adapted to reach across the full width of the belt and may be connected to the suction side of the fan 31 so that the fibers deposited on the inside of the belt will be picked olf by the suction and carried away through the pipe to be recirculated through the machine. By recirculation they may be caught on the web and form part thereof. The belt type condenser lends itself, therefore, to this type of continuous cleaning which was not readily possible with a rotary type condenser. The suction pipe 90 will remove, too, any dirt or debris that may get inside the condenser belt.

Sometimes fibers will stick to the outside surface of the condenser screen 60. There may be a discontinuous warp wire or an end sticking out. To remove these fibers, a second suction pipe 95 may be provided. This suction pipe' is also mounted outside of the air duct 30 and has an opening 96 close to the outside surface of the screen condenser. It too will extend across the full width of the screen condenser. This suction pipe, also, may be connected to the suction side of the fan 31 to recirculate any fibers picked oli the condenser belt.

For ready assembly, the entire condenser mechanism, including the internal duct may be assembled as a unit into the machine. For this purpose side plates 100 and ing ground cork or other granulated material incorporate therein. With the machine of the present invention the cork or other granulated material can be introduced while the web is being formed on the condenser thus assuring uniform distribution of the cork or other granulated material thicknesswise in the web. ji/

For feeding granular material to the machine a hopper 120 may be provided as shown in Fig. 1. This hopper (Figs. 8, 9 and 10) delivers the granulated material by gravity through an opening 121 in a casting 12,2 to a feed screw 124 that is journaled at opposite ends in the casting 122 and in an attached casing 125. Casing 125 may be secured above plate 47 of air duct 30 (Fig. l).

Journaled in the casing 125 parallel to the feed screw 124 is a uted roller 127 (Figs. 9 and 10) which has a plurality of flutes 128 formed in its periphery and extending axially of the roller. Also journaled in the casing 125 is a second feed screw 130. The two

screws

124 and 130 are of opposite hand. The casing 125 has an opening 131 in its under side registering with the utedA roller 127 and with an opening in plate 47 of air duct (Fig. 1). This opening permits delivery by the uted roller 127 of the granular material into the air duct 30 of the machine.

The granular material is fed from the hopper 120 into the outfeed screw 124 whose direction of rotation is such that the material is carried adjacent to the meter- .l ing roller 127. The granular material will spill into the 101 (Figs. 2 to 4) may be provided. These are secured by screws 102 to the

transverse duct plates

55 and 56 of the portion of duct 30 which passes through the condenser. The roll 65 is then housed in a chamber 110 formed by the

side plates

100 and 101 and the upper duct plate 55, while the roll 66 is housed in a chamber 111 formed by the

side plates

100 and 101 and the lower duct plate 56. 0n their outside surfaces the

side plates

100 and 101 have guideways 103 that are adapted to slide in guide slots 104 formed in the side plates 105 of the machine. The

rolls

65 and 66 are held securely enough in the condenser assembly; and after the condenser assembly is in position, the shafts 73 (Fig. 5) of

rolls

65 and 66, may be inserted through the

holes

106 and 107, respectively, in the side plates 105 of the machine and through the holes 108 of the end discs 71 and 72 of the rolls, and be secured to these end discs by the keys 109 which are secured in position by the set screws 75. The key ways in shafts 73, will, of course, be extendedfor the lengths of these shafts, for such assembly, and not be of the lengths denoted at 111 in Fig. 5. The holes 106 in side plates 105 are elongated to permit adjustment of the roll 65 to take up slack in the condenser belt 60 by adjusting set screws 114 whichthread into lugs 115 on each side plate 105. After assembly of the condenser in the side plates 105 the drive sprocket, pulley, or other drive means (not shown) may be fastened to the projecting end of the shaft 73 of roll 66. By sliding the supporting

side plates

100 and 101 of the condenser frame in the diagonally inclined slots 104 in the side plates 105 of the machine, then, the condenser assembly can easily be positioned in or removed from the machine.,V The

suction ducts

90 and 95 are secured in position after assembly of the condenser assembly in the machine. If desired, however, the portion of duct 90 which lies within the width of the condenser belt may be fxedly secured to plate 56 and be removable with the condenser assembly by uncoupling it from the portion of this duct which leads to the fan.

There are holes 118 in the side plates 105 which align with chamber 111 of the condenser assembly thus providing a cleanout opening extending across the whole of the frame of the machine which permits access both to the outside and to the inside of the condenser belt 60. This cleanout opening exposes the inside of the belt 60 just before it arrives at the bottom roll 66.

In many cases it may be desirable to form a web havtintes 128 of this roller. Suiiicient material should be carried at all times to more than supply the utes of the metering roller 127l for its full length. Excess material is carried from opening 121 to the far end of casing 125 by screw 124 and passes into the arcuate chamber or double elbowv 132 of the casing, where it is picked up by the return screw 130 which carries it back to the 'arcuate chamber or elbow 134 in casting 122. Here it is picked up again by the feed screw 124.

The materil that has been fed into the llutes 128 of roller 127 by the outfeed screw 124 is carried in the clockwise rotation of the metering roll 127 (Fig. l0) to opening 131 and discharged into the air duct 30 of the machine whence it is carried to condenser 60. The return screw 130 lis placed close to the metering roll 127 so that excess materials are continually wiped from the flutes ofthe metering roller before they have an opportunity to discharge at the bottom and into the air stream.

It is the purpose of this device to feed excess granular material at all times so that the iiutes 128 are always filled lengthwise and further so that the return screw 130 will remove excess material from the flutes 128 and return it to casting 122 to be fed again. The elements of the feed device rotate relative to each other to give the metering roll 127 the required R. P. M. to feed in the required pounds of material per hour. If the metering roll is speeded up, the feed screw and the return screw would also speed up maintaining the circulation of excess material.

The

screws

124 and 130 may be of opposite hand, as shown, and be rotated in the same direction, or they may be of the same hand and rotated in opposite directions. In the drawings the screw and rollers are shown as driven by

gears

135, 136, 137 secured to screw 124, roller 127 and screw 130, respectively. Any one of these gears may be drivenn any suitable manner from a motor (not shown).

While the hopper 120 is shown located at one end of the feed mechanism for the granular material, it is apparent that the hopper might be located in the center of this feed casing, in which case double-ended screws would be used which would feed outward from the center in each direction and which would return the material to the center from each end of the feed casing.

In the machine of Fig. 1, the granular material is fed into the air stream by the metering roll 127. The air stream will sweep the granular material toward the condenser screen 60 and deposit it with the fiber as the web is built up. The distance of the feeder away from the condenser screen is determined by the character of the granular material to be introduced into the web. For heavier granular material the feeder should be nearer the condenser.

ln some cases it may be desirable to introduce the granular material between two layers of ber thus form.

ing in effect a sandwich in which the central layer is granular material and the outer two layers are fibrous.

7 This may be done in a machine constructed as shown in Iigs. 6 and 7. This machine may be similar in construc-A tion to the machine previously described except for the feed mechanism for the granular material. Here feed ,and return

screws

124 and 130, and a metering roll 127 tmay be employed as before, but these are mounted in a feeder casing 125' which is inserted through the sidc plates of the machine into air duct 30 with the hopper for supplying the granular material located at one end of the casing 125 outside the machine side plates. Furthermore, a casing 140, which may be of sheet steel, is provided'around the casing 125 to split the air stream carrying the fibers into two parts, as denoted by the

arrows

141 and 142. Fiber carried in the direction 142 will be laid down on the forward reach of the condenser belt 60 at the lower end thereof. The granular material delivered by the metering roll 127 will pass through an opening 145 in the casing 140 and be delivered onto the condenser belt 60 on top of the fibrous material deposited at the lower end of the forward reach of the condenser belt. The fiber carried in the direction of the arrow 141 will then be delivered in the upper portion of the forward reach of the condenser belt on top of the granular material. Thus, the desired sandwich-like web of fiber, granular material, and fiber will be formed. Opening 145 in casing 140 may be formed between a reinforced mouth plate 146, which is secured to casing 140, and the adjacent wall of casing 125'.

If desired an opening 147 may be provided in the for ward end of the casing 140 to permit flow of air through the casing to carry the granular material onto the belt from the metering roll 127. In this case some fiber will be mixed with the granular material which may be desirable. It is possible, however, to construct casing 140 so that it is entirely closed except for discharge opening 145. In this case the granular material will be drawn out of the casing 125 by the suction of the air stream in duct 30 rushing by opening 145. It is also possible to close opening 147 and to open the ends of casing 140 to atmospheric air thereby permitting fiber-free air to enter the casing and carry the granular material through the opening 145 under suction. The opening 145 and shape of plate 146 will', of course, be varied to suit the method chosen for carrying the granular material to screen 60. In all cases, however, the plate 145 is preferably made with an undulatory upper surface, as denoted at 148 (Fig. 7) to createV some turbulence in the air stream, causing the particles of cork, as they fall from metering roll 127 to bounce, thereby insuring better deposit of the cork on the web as the web passes under the mouth 145 of lthe casing. The bottom wall 149 of the casing is elongated suiciently as shown in Fig. 7 to insure the desired suction.

It is obvious that any dry granular material may be fed into the machine as well as cork. This is advantageous where it is desired to stabilize the webs by using granular bonding agents rather than liquid bonding agents. Granular bonding agents are widelv available both in kind and use. They would not satisfactorily penetrate the product web if sprinkled on top. Therefore, webs are bonded ordinarily commercially by laminating relatively thin webs and sheets of bonding material and then inserting the laminations in platen presses using heat and pressure to form hard boards. With the machine of the present invention it is possible to introduce granular bonding agents at the time the webs are formed on the condenser thus obtaining good distribution thicknesswise on fairly heavy webs. As a result it is possible to properlv bond single thickness webs continuously. and to minimize the number of laminations in relatively thick carboards and at the same time eliminate the cut off and intermittent press operation previously required. Thus great savings in time and cost are achieved.

If the granular material is relatively fine some of it will go through the condenser screen 60 and lodge inside the condenser. This makes the cleanout described for the condenser belt 60 essential.

With the present invention, therefore, a machine has been provided which will permit manufacture of webs without limitation as to their width, in which streamline air flow through the condenser insures uniform thickness of web across the whole width within allowable tolerances, which permits ready cleaning of the condenser, and which permits of making composite webs. The machine of this invention has, therefore, manifest advantages over the prior art.

While the invention has been described, then, in connection with a number of different embodiments thereof it will be understood that it is capable of further modification, and this application is intended to cover any variations, uses, or adaptations of the invention following, in

general, the principles of the invention and including suchY proects, an endless foraminous condenser belt having both its forward and return reaches travelling through said duct, means for driving said belt including rollers over which said belt travels, atleast one of said rollers being disposed outside said duct, said machine having an opening extending therethrough transversely of said belt and between said duct and one roller and affording access to said belt for cleaning said belt, and means for effecting high speed air ow in said duct to carry fibers from said lickerin to said belt, said belt being spaced from said lickerin in the direction of ow of air in said duct.

2. A machine for forming a random fiber web, comprising a rotary lickerin, means for feeding fibrous stock to said lickerin so that in its rotation said lickerin doffs `fibers from the stock, an air duct into which said lickerin projects, an endless foraminous condenser belt having both its forward and return reaches travelling through said duct, said belt being spaced from said lickerin in the direction of ow of air in said duct, means for driving said belt including rollers over which said belt travels, at least one of said rollers being disposed outside said duct, means for effecting high speed air flow in said duct to carry fibers from said lickerin to said belt, and means disposed outside said duct for removing from said belt material caught thereon.

3. A machine for forming a random fiber web, coinprising a rotary lickerin, means for feeding fibrous stock to said lickerin so that in its rotation said lickerin doifs fibers from the stock, an air duct into which said lickerin projects, an endless foraminous condenser belt having both its forward and return reaches travelling through said duct, said belt being spaced from said lickerin in the direction of flow of air in said duct, means for driving said belt including rollers over which said belt travels, at least one of said rollers being disposed outside said duct, means for effecting high speed air flow in said duct to carry fibers from said lickerin to said belt, and means disposed outside said duct but between said duct and said one roller and within said belt for removing from said belt material caught thereon.

4. A machine for forming a random fiber web, comnrising a rotary lickerin. means for feeding fibrous stock to said lickerin, so that in its rotation said lickerin doffs fibers from the stock, an air duct into which said lickerin proiects. an endless foraminous condenser belt having both its forward and return reaches travelling through said duct, said belt being spaced from said lickerin in the direction of flow of air in said duct. means for driving said belt including rollers over which said belt travels, at least one of said rollers being disposed outside said duct. a suction pine disposed outside said duct but between said duct and "id one roller and within said belt, said pipe having a suction opening therein extending across the full width of said belt close tn the inside surface thereof to draw off of said belt material caught nn the inside surface thereof, and means for effecting high speed air flow in said duct to carrv fibers from said lickerin to said belt.

i. A machine for forming a random fiber web, comprising a rntarv lickerin. means for feeding fibrous stock tn said lickerin so that in its rotation said lickerin doa fibers from the stock. an air duct into which said lickerin nrniects. an endless foraminous condenser belt having both its forward and return reaches travelling through said dnct. means for driving said belt including rollers over which said belt travels. at least one of said rollers being disposed outside said duct. means disposed outside said duct and outside said belt for removing from said belt material caught thereon, and means for eecting high s peed air ow in said duct to carry bers from said lickerin to said belt, said belt bein spaced from said lickerin in the direction of ow of air in said duct.

6. A machine for forming a random ber web, comprising a rotary lickerin, means for feedin brous stock to said lickerin so that in its rotation sai lickerin do's bers from the stock, an air duct into which said lickerin projects, an endless foraminous condenser belt having both its forward and return reaches travelling through said duct, said belt being spaced from said lickerin in the direction of fiow of air in said duct, means for driving said belt including rollers over which said belt travels, at least one of said rollers being disposed outside said duct, means for effecting high speed air ow in said duct to carry fibers from said lickerin to said belt, and a suction pipe disposed outside said duct and outside said belt, said pipe having a suction opening therein extending across the full width of said belt close to the outside surface thereof to draw off of said belt\ material caught on the outside surface thereof.

7. A machine for forming a random ber web, cornprising a base, a lickerin rotatably mounted in said base, means for feeding fibrous stock to said lickerin so that in its rotation said lickerin dotfs bers from the stock, an air duct in said base into which said lickerin projects, a condenser support slidable into and out of said base, rollers rotatably mounted in said support, an endless foraminous condenser belt carried by said rollers, opposed duct walls secured in said support between said rollers and between the forward and return reaches of said condenser belt to provide a continuation of said air duct transversely of both the forward and return reaches of said belt when said support is in position in said base,

. and means operable when said support is in position in said base to cause air flow in said duct from said lickerin to and through said condenser belt.

8. A machine for forming a random iber web, comprising a base, a lickerin rotatably mounted in said base, means for feeding fibrous stock to said lickerin so that in its rotation said lickerin dois bers from the stock,

an air duct in said base into which said lickerin projects, a condenser support slidable into and out of said base, a pair of spaced rollers rotatably mounted in said-support, an endless foraminous condenser belt mounted to travel over said rollers, opposed duct walls secured in said support between said rollers and between the forward and return reaches lof said condenser belt to align with corresponding opposed walls of said air duct, when said support is in position in said base, and thereby form a continuation of said `air duct, and means operable when said support is in position in said base to cause air ow in said duct from said lickerin to and through said condenser belt, said support being slidable into and out of said base in a direction transverse of said air duct, and said support and base having interengageable guide surfaces for the purpose of guiding the sliding movement of said support.

9. A machine for forming a random ber web, .comprising a base, a lickerin rotatably mounted in said base, means for feeding brous stock to said lickerin so that in its rotation said lickerin dois bers from the stock, an air duct in said base into which said lickerin projects, a condenser support slidable into and out of said base,

a pair of spaced rollers rotatably mounted in said support, an endless foraminous condenser belt mounted to travel' over said rollers, opposed duct walls secured in said support between said rollers and between the foi'-- ward and return reaches of said condenser belt to align with corresponding opposed walls of said air duct, when said support is in position in said base, and thereby form a continuation of said air duct, said condenser belt when positioned in said base being inclined diagonally to the direction of ow of air in said air duct, and means operable when said support is in position in said base to cause air ow in said duct from said lickerin to and through said condenser belt, said support being slidable into and out of said base in a direction parallel to the direction of travel of the forward reach-of said condenser belt, and said support and base having interengageable guide surfaces for the purpose of guiding the sliding movement of said support.

10. A machine for forming a random ber web, comprising a base, a lickerin rotatably mounted in said base, means for feeding brous stock to said lickerin so that in its rotation said lickerin doffs bers from the stock, an air duct in said base into which said hckenn pro ects, a condenser `support slidable into and out of said ase, a pair of spaced rollers rotatably mountedv in said v support, an endless foraminous condenser belt mounted totravel over said rollers, opposed duct walls secured in said support between said rollers and between the forward and return reaches of said foraminous belt, to align with corresponding opposed walls of said airduct when said support is in position in said base and thereby form a continuation of said air duct, a suction pipe mounted doifs fibers from said stock, an endless foraminous condenser belt, means for driving said belt, an air duct into which said lickerin projects and through which both the forward and return reaches of said condenser belt extend, means for creating an air stream in said duct which ows from said lickerin to and through the reaches of said condenser belt, means disposed between said lickerin and said condenser belt for dividing said air stream, and means mounted between the divisions of said air stream for feeding material onto said condenser belt.

l2. A machine for forming a composite random web, comprising a rotary lickerin, means for feeding fibrous stock to said lickerin so that in its rotation said lickerin doffs bers from said stock, an endless foraminous condenser belt, means for driving said belt, an air duct into which said lickerin projects and through which both'the forward and return reaches of said condenser belt extend, opposed walls of said air duct diverging from one another between said lickerin and said condenser belt and the forward reach, at least, of said condenser belt travelling diagonally across said air duct, means for creating an air stream in said duct which travels from said lickerin to and through the reaches of said condenser belt, means disposed between said lickerin and said condenser belt for dividing said air stream, and means mounted between the divisions of said air stream for feeding material onto said condenser belt.

13. A machine for forming a composite random web, comprising a rotary lickerin, means for feeding fibrous stock to said lickerin so that in its rotation said lickerin doffs fibers from said stock, a movable foraminous condenser, means for driving said condenser, an air duct into which the lickerin projects and which extends from said lickerin to said condenser, and means for introducing a material into said air duct between said lickerin and said condenser, said last-named means comprising a casing having a` mouth communicating with said air duct and an opening through which said material may be supplied to said casing, a rotary feed screw journaled in said casing and communicating with said opening to convey material away from said opening, a rotary fluted ymetering roller for receiving material from said feed screw and delivering it through said mouth into said air 14. A machine for forming a composite random web,l

comprising'a rotary lickerin, means for feeding brous stock to said lickerin so that in its rotation said lickerin doifs bers from said stock, a movable foraminous condenser, means for driving said condenser, an air duct into which the lickerin projects and which extends from said lickerin to said condenser, and means for introducing a material into said air duct between said lickerin and said condenser, said last-named means comprising a casing having a mouth communicating with said air duct and an opening through which said material may be supplied to said casing, a rotary feed screw, an axially tinted metering roller, and a rotary return feed screw journaled in said casing in parallelism with one another, said feed screw communicating with said opening and operating to deliver the material from said opening to said metering roller, said metering roller registering with said mouth to deliver material into said air duct, said metering roller and means for rotating said metering roller and said two comprising a rotary lickerin,

screws, said casing being closed at both ends whereby excess material is returned by said return feed screw to said feed screw to be fed again to said metering roller.

l5. A machine for forming a composite random web, means for feeding fibrous stock to said lickerin so that in its rotation said lickerin doffs bers from said stock, a movable foraminous condenser, means for driving said condenser, an air duct into which the lickerin projects and which extends from said lickerin to said condenser, means disposed between said lickerin and said condenser for dividing a stream of air flowing in said air duct, means mounted between the divisions of said air stream for feeding a material into said air duct, said last-named means comprising a feed screw, and a uted metering roller, said feed screw being rotatable to feed the material from a source of supply to the flutes of said metering roller, and said metering roller communicating with said air duct, and means for rotating the feed screw and said metering roller to effect said feed movement.

16. A machine for forming a composite random web, comprising a rotary lickerin, means for feeding fibrous stock to said lickerin so that in its rotation said lickerin dos fibers from said stock, a movable forarninous condenser, means for driving said condenser, an air duct into which the lickerin projects and which extends from said lickerin to said condenser, means disposed between said lickerin and said condenser for dividing a stream of air owing in said air duct, means mounted between the divisions of said air stream for feeding a material into said air duct, said last-named means comprising a casing, a rotary feed screw, a rotary tluted metering roller, and a rotary return screw, said two screws and said metering roller being journaled in said casing in parallelism with one another with the metering roller being disposed between the two screws, said feed screw being rotatable to feed the material from a source of supply to the flutes of said metering roller, said casing having a slot in one wall through which material may be delivered by said metering roller into said air duct, said slot extending axially of said metering roller but being narrower than the diameter of said metering roller, said return screw operatingY to return excess material to said feed screw, and mlans for rotating the two screws and said metering ro er.

References Cited in the le of this patent UNITED STATES. PATENTS