CA2191618A1

CA2191618A1 - Apparatus for spreading chips, especially elongated chips in the production of oriented-chip board

Info

Publication number: CA2191618A1
Application number: CA002191618A
Authority: CA
Inventors: Klaus Gerhardt
Original assignee: G Siempelkamp GmbH and Co KG
Current assignee: G Siempelkamp GmbH and Co KG
Priority date: 1995-12-01
Filing date: 1996-11-28
Publication date: 1997-06-02
Also published as: DE19544866A1; FI964747A; SE9604347L; ITMI962511A1; ITMI962511A0; FI964747A0; SE9604347D0; IT1286475B1

Abstract

An apparatus for spreading chips, especially elongated chips as part of a chip-oriented chip board production process, has a multiplicity of parallel stationary vertical wall elements defining shafts between them and an inverted U orienting element above the wall elements and receiving the wall elements. The mechanism for imparting periodic motion of the orienting elements can include a crank or the like which preferably is adjustable as to the stroke and the lengths of the U shanks are at least equal to the vertical stroke of the orienting elements.

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Description

2 1 9 l G ~ 8 APPARAlUS ~OR SPR~ADING CHIPS, ~;~ r.y ~l~)NGA~r~D C~IPS IN 2'~R
Pf~ODrJCq'Io~ OF OR~ ~CHIP ~OARD

SPF~CTFICATION

~LD OP T~ INV~N~ION

My present invention relates to an apparatu~ for spreading chips, e~p~cially elongated chipQ, ln the production o~
oriented-chip board and like boards fabricated from wood material. More partlcularly, the invention r~lates to the orlentation of ~uch chip~.

~ qR~UND OF T~E ~NVBN~ION
~n the production of chip board and e~pecially so-call~d OSB board, i.e. oriented ~trand board, the OSB strands generally have a consid~rable length, width and thic~ne~.
To fabricate ~uch boards in a proces~ for making chip board, a prellminary ~tep i8 the spre~ding of the chips, especially elongated or longitudinally-extending chips, upon a recei~ing surface on whlch the layer o~ chips can be subjected to compre~sion and heating ~o consolidate the chlps of the layer into the pre~sed board.
The ~ood chip~ may ~e combined with a binder, especlally a heat-activatable ~inder, and the layer may be ~ub~ected to a prepre~sing or inltially pres~ing ~tage and to one 219161~

or more ~ubseguent pre~s1ng ~tage~ or a final prea~lng stage and any of the preYsing stages may b~ accompanied by hea~ing. In general, there~ore, a process involving hot pres lng ~ carried ou~ .
Since the str~ngth of the resulting strand depend~ upon the orientation of the chip~, the spreadlng stage involve~
pa~sing the ca~cade of chip~ through an orlenting ~ystem which may comprise a multiplicity of vertical wall-~orm~ng elements which can be fixed and can cooperatQ with orienting elements, the lo wall-forming element~ defining shaft-llke pa~sage botween th~m and the or~entlng elements having a drive enabling a periodlc movement to be applied to the orientlng elements, The chips them~elves can have ~lgn~ficant dimenslonQ
and may be bar-~haped elementq, for example, wlth a length of loO
to 350 mm, width~ of 5 to 60 mm and thickn~ses of 1.5 to 6 mm (~ee German patent documents DE 195 30 211.9 Al and DE 195 30 212.5). The chip board which ls fabricated may have sub~tantially greater thlckne~se~ and can be cut up to ~orm beams and the like. It wlll be self-under~tood th~t an optimum orientation o~ the chip~, espec~ally -~uch ~zable elongated chips, i~ de~irable and contributing to such orientatlon i~ the width of the ~haft-like columns between the wall elements traverced by th~ chip~ and the d~men~ions of the chlps on the one hand and the nature of the movement imparted to the or~enting elements on the other hand. In the past the mo~ement has ~191bl~

con6isted of bidirectional movement with a back and forth mov~m~nt along a line for each orienting ~lement.
Improvement in the degree of orientatlon ha~ been found to b~ neces~ary in order to provide compact ~igh ~trength beams or 8tr~nds by the chip-orienting p~oce6~.
In one app~ratus as de6cribed ln German patent document DE 17 03 832, the orienting elements have th~ linear back and forth movement de~cribed above w~th succes~ive orienting element~
being moved counterphasally, i.e. in equal but oppo~ite dir~ctlons. N~ second component of the movement i8 applied. The orienting elements themsQlves are bar-6haped member~ ln the form o~ rods or channel~ with short ~hanks. The deg~ee o~ orientation which result~ from this apparatu~ is ~at~sfactory only in some cases and turn~ out to be un~at~s~actory when the sha~t-~orming passages betwe~n the ~all element~ ar~ relativQly wlde as i9 necessary to accommodate high t~roughputs of th~ c~ip material.
In the pa~t, there~o~e, such apparatu~ has not be~n u3ed 8ucce88~ully for high throughput-~.
When high throughputs of the chips was required, the ~preader generally compri~ed rotating tooth circular wheel~
(German patent document DE 11 74 058) and elliptical or like disks ~German patent document D~ 37 06 272 Al). The high throughput~ obtainable with these latter sy6tem~, however, i8 at the expense of a high degree of orientation.

2)9i~18 O~J~CT8 OP THF INV~N~I0~
lt is, thorQfore, the principal object of the pressnt invention to provide an appara~u~ of th~ type first de6crlbed which ls no improved that hlgher throughput~ can be obtained at the sams time as thor~ ia an improvement in the degree of orientation.
Another ob~ect of thi~ inventlon ls to provide a spreader for elongated chips, especially wood chips for the fabrication of chip board, whereby drawbacks ln earlier orient$ng and chip-spreading system~ can be obviated.

8UMMARY OP TH~ INV~N~0~
T~ese ob; eCtB a~e attained, in accordance wlth the invention ~y applylng to the orienting ~lement~ a movement which include3 a displac JflL component in the dlrectlon of elongation o~ the element~, i.e. in the horizontal direction and along the wall element~ and orienting element~ and, in addition, a vertical movement component which i~ perpendicular to the longitudinal directlon. According to thQ ln~entlon, moreo~er, the orienting elements are inverted U-~haped members whose U s~ank~ are of a length at least equal to t~Q vertical movement component, i.e.
the component of movement in the direction transver3e to the longitud~nal direction.
FurthermorQ, the shaft-forming wall elements are ~o dispo~ed that they extend into the orienting element, l.e.
2 5 between the shank~ thereof.

21916~8 More particularly, an apparatus for spreading chips in con~unction wlth the production of chlp board and ~specially elongated chips of wood can compri8e:
a multiplicity of mutually p~rallQl, horizontally ~paced vQrtical elongated sha~t-~orming wall elementQ between which chip~ for forming a chip board can cascade toward a receiving sur~ace;
a respective elongated orienting el~ment for Qach of tho wall element~, each of the orienting element~ being of lo ln~e~t~d-U ~ection w~th platQ-shaped shanks flanking the respectlve wall element and ~ach wall element extending into the respecti~e lnverted-U be~ween the shan~s t~ereof;
a drlve ~or periodically dlsplacing the orienting element-~ with a vertical component o~ displacement and a longitudinal component of di~placement perpendicular to the vertical component of displacement and ln a directlon of elongation of t~e wall and orienting element~, the shanks having lengths at lea~t eq~al to the vertical dlsplacements of ~e orienting elements.
~he drlve for periodically displac~ng the o~i~nting element~ with th~ two components can readlly be a crank drive.
It has been found to be advan~ag~ous to provide mean~
for adju~ting the di~placement of the orient~ng elements, i.e.
the amplltude~ of the a~orementioned co~pon~nts which ad~u~tment serves to optlmlze thc degree of orientation ~or scattering of chip~ o~ a predetermined lenqth.

21916I~

Indeed it has ~l~o been found to be advantageou~ to provide the orienting elements and the respectiv~ wall elements in stages one above another, i.e. in a ~tacked relation~hip but 80 that the spacing between the elements diminishes downwardly S from ~tage to stage a~ t~aver~ed by the cascade of chip3.
The apparatus of the invention allows an extremely high throughput of chips without any negative effects as far a~
orientation of the chips i~ concerned. In other words ~he apparatus achieves a high degree o~ orientation while lo nevertheless allowing a high throughput.

JRIEP DE~CRIPTIO~ OF THE DRA~N~
The above and other object~, ~eatures, and advantagec will become more readily apparent from the following de~cription, reference being made to the accompanylng drawlng ln which:
FIG. 1 i~ a diagrammatlc vertical section of an apparatus for orlenting wood chips taken in a plane perpendicular to the longit~dinal dimension in which the wall elements and the orienting elements extend;
~ IG. 2 is a vlQw taken along the line II - II of FIG.
1:
FIG. 3 is a perspective view diagra~matically illustrating a drive for the orienting elements;
FIG. 4 i~ a fragmentary ~levational view illu~trating how the ~troke of the crank drivQ is adjustable; and 2191~l~

FIG. S $~ a block diagram illustratlng the production of chip board utilizang the orientation apparatu6 of the invention.

~P~C~FIC ICP~TION
- S R~ferring flrst to FIG. 5, an initial stage in the production o~ ch~p board i5 the mat formation and orientation stage 10 which is followed by one or more hot pre6s~ng stages 11 and any trimming and cutting ~tages 12 which ~ay bc required. As a part of the mat formation and orientatlon stage, the chips, wh~ch are dellvered by a chip supply 13, i.e. a hopper and metering ~ystem, can be subjected to orientation a~ they are ~cattered on a receiving 6urface 14 which can be a belt or tray carrying the mat to and through the pressing stage or ~tages and ~eparated from the pre6~ed board be~ore it enter~ the trimm~ng stage. The chip~ can be elongated splinter~ or particles of wood when the system is used for the production o~ chip-oriented chip board and like wood particle board~.
For the orientation purposes, a multiplicity of wall elements or plates 1 are provided and these wall elements are transversely spaced apart and extend longitudinally in a direction perpend$cular to the plane of the paper in FIG. 1.
Bach ~uch wall element 1 is a6~0ciated wlth a slm$1arly elongated orientlng element 2, the orienting elements being connectQd to a drive 3 (FIG. 3) impartlng a periodic movement to the orienting elements. One of the components of moYement ls in the verti~al ~1916~

dlrcctlon a~ repre~ented by the arrow~ 15 ln FIG. 1 whlle the other i~ a baclc and forth movement perpQndicular to the plane of the paper, i.e. in the dlrection ~ repreQented in FIG. 2, the arrows lS rcpre~ent the displacement component b in FIG. 2. A
composite o~ the two perlodlc movsments wlth component~ a and b is a circular movement as represented by the arrow 16 in FIG. 2.
The orienting e1ements 2 them~elvec are lnverted U-~ection members 4 who~e shanks 5 are at least of a l~ngth egual to ~he displacement component b. Each two walls 1 act as wall~ 6 of a ~ha~t 17 through which the chips ca~cad~ downwardly and these walls engage ln the lnverted U members 4. Each combination of orienting elements 2 with the shaft-forming wall ~lement~ 1 de~ine clo~ed shaft walls 7.
A6 can be ~een from FIG. 3, the drlve 3 i~ a crank lS drive which can be driven by a motor 18. As can be ~een from F~G. 4, the amplitude or throw of the crank drive can be varied by the rotation of sleeves 19 whlch threadedly engage oppositely threaded rod portlon~ of the crank so that rotatlon of each sleeve 19 in one direction will reduce the throw T of the eccentric while rotation of the sleeve in t~e opposite direction will increa~e the throw o~ the eccentric and hang the amplitude of the movements of the orlenting element 2 ln the d~rection of the two component~.
From FIG. 1 it wlll be apparent that each ~et of wall element~ 1 and the re~pectlve orienting element~ 2 lie at a re3pective le~el in ~he shafts between the walls 20 and 21 and 219l618 the level~ have di~ferent ~pacings S of the wall elements l from one another, the lower level having the ~mallQr spacing. With this apparatu~, the wood chips, whlch can be comparatively long ~plinter~, are readily aligned in the longitudinal direction, S i.e. with their chip axes parallel to ths wall element~ 1 and ~ubstantially horizontally to en~ure e~peclally high strength of the chip board. ~he alignment is a~sured even with very high throughputs of the chip material.

Claims

1. An apparatus for spreading chips in the production of chip board, comprising:
a multiplicity of mutually parallel, horizontally spaced vertical elongated shaft-forming wall elements between which chips for forming a chip board can cascade toward a receiving surface;
a respective elongated orienting element for each of said wall elements, each of said orienting elements being of inverted-U section with plate-shaped shanks flanking the respective wall element and each wall element extending into the respective inverted-U between the shanks thereof:
a drive for periodically displacing said orienting elements with a vertical component of displacement and a longitudinal component of displacement perpendicular to the vertical component of displacement and in a direction of elongation of said wall and orienting elements, said shanks having lengths at least equal to the vertical displacements of said orienting elements.

2. The apparatus defined in claim 1 wherein said components are superimposed upon one another to impart a generally circular movement to each of said orienting elements.

3. The apparatus defined in claim 2 wherein said drive is a crank drive.

4. The apparatus defined in claim 1, further comprising means for varying an amplitude of the displacement of said orienting elements.

5. The apparatus defined in claim 1 wherein said wall elements and said orienting elements are located in an orienting that in a plurality of levels one above another each of which comprises a respective multiplicity of wall elements and respective orienting elements for each of the wall elements, the transverse spacing of said elements varying from level to level and being smaller from an upper level to a lower level.