US 3187386 A
Description (OCR text may contain errors)
June 1965 D. L. SCHUBERT ETAL 3, 7,
FELTING APPARATUS Filed June 25. 1960 2 Sheets-Sheet 1 5 1 .Dale L.Schube r+ Roberz WRiZey mmvrons BY a June 8, 1965 D. SCHUBERT ETAL 3,187,386
FELTING APPARATUS Filed June 25. 1960 2 Sheets-Sheet 2 4e- 52M; L 56 48 50 6 1 "'1, I I L DaleLSchub r i" 5-29 Roberf WRiley INVENTORS United Statesv PatentO Co., Inc., Tacoma, Wash, a corporation of Washington Filed June 23, 1960, Ser. No. 33,376 2 Claims. (Cl. 19-455) This invention relates to apparatus for forming sideedge trirmned felted mats. It relates particularly to apparatus for producing felted mats of lignoce'llulosic pieces useful in the production of Wood composition board.
In the manufacture of wood composition board, it is usual practice to form a felted, binder-containing mat of wood fibers, chips, particles, or milled shavings and then pressing the mat until the desired degree of consolidation has been achieved.
A difficulty inherent in this procedure is that of providing a mat of uniform thickness, since non-uniformity of mat thickness is reflected in non-uniformity of density and other properties of the finished product.
It is particularly diflicult to produce a mat of uniform thickness using the various high-capacity,- continuous felters, in part because of irregular action of the felters and in part because of the tendency of the finely divided lignocellulosic felting stock to form flocks and clots which,
when deposited on the felt, produce undesirable irregularities.
This difficulty is particularly inherent in the operation of the commonly used wig-wag type fel-ters wherein the material to be felted is passed rapidly through a crankdriven, oscillating spout and deposited on a moving conveyor bet-Ween longitudinally arranged deckles.
The mat formed by such a fclter often is thicker at the edges than it is in the center portion since the flow of material through the spout is continuous, but the spout motion is eccentric during direction reversal at. the end of each stroke. Also, the material being felted tends to hang up on the side walls of the deckles, dropping down onto the margins of the mat at irregular intervals whenever a sufficient (Weight has accumulated.
The usual attempt to correct this difiiculty by scalping the upper surface of the mat is not entirely successful. Even though seal-ping results in the formation of a mat of uniform thickness, it still may be of non-uniform density since the thicker edge portions of the mat have been consolidated irregularly by the weight of the accumulated material.
It is a general object of the present invention to provide apparatus overcoming the foregoing deficiencies of prior art felting apparatus and producing as a final product a mat or felt of uniform thickness and density which may be consolidattxl to form afinal product of uniform properties. i
Other important objects of this'invention are the provision of felting apparatus which is easily adjustable to form felted mats of predetermined width and which is adapted to the high-speed, continuous production, without loss of rawmaterial, of feltedmats having side edges which are smooth and straight.
In the drawings:
FIG. 1 is a front elevation, partly in section and partly broken away, of a wigewag felter which may be used as a component of the presently described edge trimming apparatus;
FIG. 2 is a side elevation of the edge trimming unit used in combination with felting apparatus such as that of FIG. 1; and I FIG. 3 is a sectional view of the edge trimming unit of FIG. 2, taken along line 3-3 of that figure.
In its broadest aspect, the edge trimming felting apparatus of our invention comprises in combination a mat conveying means, felting means stationed for forming a felted mat on the conveying means, and mat trimming means stationed downstream from the felting means for trimming away the longitudinal side margins of the mat.
The mat trimming means preferably comprises saws stationed inwardly a predetermined distance from the longitudinal side edges of the mat and working'in conjunction With disintegrators which disintegrate the mat margins trimmed away by the saw. Collecting and conveying means are provided for collecting the trimmedaway, disintegrated material and conveying it back to the felter. I
The raw material which may be employed in the herein described edge trimming felting apparatus broadly comprises any material of the class from which felted mats are formed. Thus it may comprise plant materials, such as 'bagasse or straw reduced to the form of small pieces.
Preferably, however, it comprises wood in the form of vided with a flexible section 1-4 inside the tfelter box and is supported in a yoke 16 pivoted on shaft 18.
The spout is oscillated between the illustrated dotted line position-s by means of a motor 2t driving a crank 22 through gear box 24.- Connecting rod 26 is connected pivotally to a lever 28 which in turn is rigid to yoke 16;
Crank 22 drives spout 1-2 in characteristic wig-wag fashion, delivering a continuous flow of raw material between stationary deckles 39 arranged along the longitudinal side edges of a traveling conveyor 32. The latter preferably comprises an endless screen or other foraminous member driven by pulleys 34. The screen traverses a suction box 36 located directly below spout 12 and. creating an air flow which assists in depositing a felt 40 on the screen. 7
Because of the eccentric motion of spout 12, and because of fall-off of accumulated material from the side walls of decldes 30, the longitudinal margins of felt 40 may be thicker and less uniform than the central portion of the felt. Accordingly means are provided for trimming away these margins to the extent necessary to remove the built up areas and form a mat of the desired width. The means employed for this purpose are illustrated in FIGS. 2 and 3. x 1 7 After passing beneath a conventional scalping roll, the presence of which is optional and not illustrated, and with Y or without having been prepressed, mat 40 passes through trimming units preferably provided in tandem, one work ing on each margin ofthe mat; The trimming units may be of identical construction and are supported on a substantial bar 42 mounted on the frame of the apparatus. Each unit is 'adjustably fixed to the bar by means of a clamp 44. This provides a lateral adjustment useful in determining the Width of the mat to be produced.
' Clamp 44 supports a vertical bar 46 which is welded to the housing of a motor 48.
. Keyed to one end of the motor shaft is a vertical saw 50, the plane of which parallels the direction of travel of the mat. The vertical position of the saw is such that its lower edge is adjacent, but does not touch, conveyor screen 32.
The other end of the shaft of motor 43 drives means for disintegrating the side margin of the mat cut away by saw 50. In the illustrated form of the invention a hood 52 supported from vertical bar 46 in turn rotatably mounts a spiked disintegrating roll 54- connected to the Patented June 8, 1965 3 shaft of motor 48 by belt 56. Operation of the disintegrating roll synchronously with saw 50 eifectively disintegrates the margin cut away by the latter.
Means then are provided for collecting and conveying away the disintegrated material. Communicating with hood 52 is a conduit 58 including a flexible section 60 to accommodate lateral adjustment of the edge trimming unit. Conduit 58 feeds a larger conduit 62 which recycles the trimmed-away, distin-tegrated material to the source feeding inlet duct 12 of felter 10.
It is to be understood that the form of our invention herein shown and described is to be taken as a preferred example of the same and that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of our invention or the scope of the subjoined claims.
Having thus described our invention, we claim:
1. In felting apparatus for making mats of lignocellulose particles and including mat conveying means, deckle means adjacent the sides of the mat conveying means for confining the longitudinal sides of a mat formed on the conveying means, and felting means arranged to deposit lignocellulose particles on the conveying means between the deckle means, and wherein the apparatus is characterized by forming a mat having an intermediate portion of substantially uniform thickness and side portions of substantial width which are of different thickness than said intermediate portion: the combination therewith of edge trimming apparatus comprising laterally spaced cutter means mounted above the mat conveying means a substantial distance inwardly of the planes of the deckle means for severing the said side pontions of the mat from the intermediate portion, the disintegrating means positioned laterally outward and downstream of the cutter means for disintegrating the severed side portions of the mat, and conveyor means adjacent the disintegrating means for returning the particles to the felting means.
2. The combination of claim 1 wherein the disintegrating means comprises a roll associated with each cutter means and having thereon a plurality of laterally spaced spikes for engaging and disintegrating the severed side portions of the mat.
References Cited by the Examiner UNITED STATES PATENTS 2,165,280 7/39 Lannan 156--375 2,295,971 9/42 Savidge l5428 2,743,758 5/56 Uschmann 1541 2,822,028 2/58 Himmelheber et al 15636 2,925,117 2/ 60 Moore et a1. 15429 EARL M. BERGERT, Primary Examiner.
CARL F. KRAFFT, Examiner.