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Патент USA US2116168

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May 3, 1938.
Filed ’ July 11 , 1933
' 4206
Patented May 3, 1938
James Fish, Bristol,“ Pa. , and Arnold John vBarea,
Berlin, N. H., assignors to Brown Company,
N. H., a corporation of Maine
Application July 11, 1933, Serial No. 679,906
6 Claims. (Cl. 92-45)
This invention relates to a method of and ap
water from its lowermost layer to form a pulp
paratus for improving the formation of a pulp web
against the wire While the upper layer of the
web on a Fourdrinier wire of a paper-making stock still retains approximately its original con
sistency. The omission of a table roll leaves a
Heretofore it has been common practice to im
substantial stretch of unsupported wire at this
part a lateral shake to the portion of the Four
critical point ‘in the formation of the pulp ‘web.
drinier wire extending over the table rolls. Thus, The unsupported stretch of wire magni?es the
the ?bers in the pulp stock which ?ows over the vibrations received through the shake rails and
“ breast roll onto the Fourdrinier wire, and which
no tend to aline themselves withthe direction of
?ow, are agitated in such a way as to cause many
of the ?bers to assume crisscross positions in the
web whichvis formed on the wire by the drain
age of white water from the stock deposited
M thereon.) Under the best of conditions, however,
adjacent table rolls so that the stock on this por
tion-of the wire is strongly agitated in such a 10
manner as to form standing waves of a height
many times the amplitude of the vibration.
These waves‘ effectively prevent the formation of
?ber bunches in the liquid upper portion of the
sheet, and break up any bunches of ?berswhich
the paper sheet resulting from a web thus formed may have collected while traveling from the wet
is subjected to ripples or non-uniformity of thick , end
of the wire to the point of agitation.
ness of sheet, especially in the case of heavy
For a more complete understanding of the
sheets, or of free stock. This can readily be ob
invention, reference may be had to the descrip
by holding the sheet
of paper to the
igh .
tion thereof which follows and to the illustra- I
tion of an embodiment thereof on the drawing,
It is an object of the present invention to im
prove the uniformity of a heavy paper sheet by
the particular kind of agitation of the web ar
ranged to take place at the particular stage in
its formation. According to the invention, a
liquid sheet of pulp stock is run onto the Four
Fourdrinier paper-making machine, many of the
customary parts being omitted to avoid confusion
drinier wire in the usual manner and may be sub
1 on a larger scale.
jected to the usual lateral shake. As the sheet
30 of stock progresses with the movement of the
wire, the lowermost portion of the sheet directly
against the face of the wire loses its white water
?rst so that an incipient layer or mat of ?ber is
formed against the face of the wire before the
35 upper portion of the liquid sheet of stock has
on which
Figure l is a side elevation of the wet end of a
of detail.
Figure 3 is a section on the line 3-3 of Fig
ure 2.
Figure 4 is a section on the line ‘fl-1i of Fig- 30 ‘
.ure 2.
Figure 5 is a section on the line 5—5 of Fig
Figure 6 is a section on the line 6-43 of Fig-
lost any appreciable amount of its white water. ‘ ure 2.
At this stage in the formation of the web, the
sheet is subjected to a vibration of such a nature
as to set up a series of standing waves in the
40‘ aqueous upper portion of the sheet. This partic
ular type of agitation has the effect of offsetting
the tendency on the part of the ?bers in the liq
uid upper portion of the sheet to collect in soft
bunches before they are deposited in the pulp
45 web by the escape of the white water by which
they are carried. Thus the. ?ber distribution in
the upper portion of the sheet is such as to
result in a substantially uniform paper sheet.
Vibrations adaptedto attain these results may
50 be set up by imparting to the shake rails and
the table rolls supported thereby a rapid vertical
oscillation of small amplitude, say a few hun
dredths of an inch. Furthermore, one or more
of the table rolls may be omitted at the point
where the sheet of stock has lost su?icient white
Figure 2 is an elevation of a portion of Figure
As illustrated in Figure 1, the invention may be
embodied in the wet end of aFourdrinier paper
making machine which includes a?xed base ID
from which a number of supporting standards H
extend upwardly to support a pair of ?xed side
bars i2. These side bars support a pair of shake
rails which, as indicated in Figure 1, may each
consist of two separate parts l4, Ill. The part
ll of each shake rail, which is nearer to the 45;
breast roll I6, is loosely supported for limited
vertical movement. To this end, each of the side
bars I2 is provided with a number of hangers 11.
Each han‘ger is vertically slotted as at l8 so as
to receive therethrough a bolt 20 having a head 50
2|. A spacer block 22 is provided next to the
head 2|. This spacer block, if desired, may be
integral with the bolt itself. The spacer, block
rides in an aperture 23 in the shake rail l4 and
cooperates with a nut 25 on. the bolt 20 to clamp - .
the bolt ?rmly to the hanger H in a vertically
adjusted position. The head 2| of the bolt over
laps the sides of the aperture 23 so as to hold the
rail M in position, but at the same time to allow
a limited free vertical movement on the part of -
the rail.
The portions ii of the shake rails, remote from
the breast roll l6, may be suitably ?xed to
hangers IT. The shake rails are provided with
'10 bearing members 30 for table rolls 3| over which
a wire screen 32 extends. The apparatus may be
provided vwith the usual head box 33 and with one
or more slices 34.
Vertical shaking. movement is
imparted to the loosely mounted portions H of
before they are deposited in the pulp web. Thus
heavy sheets can be made of free stock with a
high degree of uniformity of distribution of ?bers
through the entire thickness of the sheet.
Various ‘modi?cations and changes may
made in the particular embodiment of the
vention herein shown and described without
parting from the spirit or scope thereof as
?ned by the following claims.
We claim:
1. In 'a paper-making machine, a breast roll, a
pair of shake rails, a series of table rolls jour
naled on said rails, said rolls being arranged with
a substantial gap in the series near the breast
15 the shake rails by any suitable apparatus. As
shown, a block 35 is ?xed to each shake rail por
roll, and means for vertically oscillating the rails
and table rolls in the vicinity of said gap.
which is mounted on an eccentric member 4|.
The eccentric member II is mounted on an ec
at a point where a substantial fraction of the pulp
2. In a paper-making machine, a Fourdrinier
tion l4. Each block contains a socket 36 which
cooperates with the upper end 31 of a pitman 38 7 wire adapted to receive dilute pulp stock thereon,
to form a ball and socket joint ‘so as to permit a pair of shake rails, a series of table rolls on
20 the customary lateral shake. The pitman 38 ~ said rails supporting said wire, said rolls being
extends upwardly from an eccentric strap 40 arranged with a substantially greater than
centric sleeve 42, which in turn is mounted von a
drive shaft 43. Since both the members 4| and
42 are eccentric, the amplitude of vibration may
be altered by adjusting the angular relation be
tween the two eccentric members so that their
eccentricities will either augment or neutralize
30 each other to a greater or less extent according
to the angular relation. As indicated in Figures
1v andl2, one or more of the table rolls may be
omitted. The particular roll or rolls to be
omitted will, in any particular case, depend upon
35 the amount and characteristics of the pulp stock
‘supplied to the machine. It is desirable to omit
a roll at the point where the lowermost stratum
of vthe'stock on-the wire has lost enough of its
white waterto form a web on the screen, but the
upper stratum of stock is still liquid but is at the
point of depositing its ?ber on the web which is
forming. The location of the gap between suc
cessive table rolls will depend upon the nature
of-the stock employed, a web being formed more
rapidly from pulps of somekinds than from pulps
of other ‘kinds. In operating the mechanism,
the usual horizontal shake may be imparted to
the pulp stock by means well known in the art
but not herein illustrated. In addition to the
50 customary lateral shake, a vertical shake may be
imparted by the eccentric mechanism shown and
described, the amplitude of such vibrations being
of the order of a few hundredths of an inch.
The frequency of vibLation may vary within con
siderable limits and will in any particularcase
depend upon the conditions of operation. In
most cases frequencies between 600 and 2000 per
customary. gap in the series near the breast roll
stock on the wire, when the machine is in opera
tion, has drained sufliciently to form a web next
to the wire while the upper stratum of stock com
prising a substantial fraction of the pulp is liquid,
and means for imparting a rapid vertical oscilla
tion to ‘the rails.
3.<In a paper-making machine, a supporting 30
frame, a pair of side rails mounted on said frame
for limited vertical movement, a series of table
rolls j-ournaled on said rails and arranged with a
gap in the series near the breast roll at least
twice as wide as the usual space between suc 35
cessive rolls at the same place, and means for
imparting a vertical oscillation to saidrails and
to the table rolls carried thereby.
4. Ina paper-making machine having a breast
roll,“a stationary support frame, a pair of shake 40
rails supported in said frame, each said rail hav
ing two separate parts, the parts remote from‘the
breast roll being adjustably ?xed to said frame,
the parts near the breast roll being loosely sup
ported by said frame for limited vertical move 45
ment, table rolls carried by said shake rails, the
rolls on the loosely mounted portions of the rails
being arranged with a substantial gap between
two of the rolls, and means for imparting to said
loosely mounted‘ rail portions a vertical vibration 50
of small amplitude.
5. In a paper-making machine, a series of table
rolls, a pair of shake rails carrying said rolls and
loosely mounted for limited vertical movement.
said rolls being arranged with a substantial gap
between two of the rolls, and means for impart
ing vertical oscillation to said shake rails and the.
-on either side of the gap- This wire screen is
65 under considerable longitudinal tension, and the
rolls thereon, said means including a rotatable
shaft, an eccentric mounted on said shaft, an
eccentric strap on said eccentric, and a p‘itman
connecting said strap and a shake rail.
6. A method of forming a relatively thick ‘pulp
web, which comprises removing from a Four
drinier machine one of the table rolls at a point
where a substantial fraction of the stock on the
wire has formed a mat and a substantial fraction
through the shake rails and table rolls, become
considerably ampli?ed in the unsupported stretch
of the stock still retains its original consistency,
operating the machine in the usual manner, and
minute give satisfactory results. The vibrations
are imparted to the loosely mounted portions ll
60 of the shake rails and tothe table rolls which
are supported thereon.
By omitting one or more
of these table'rolls, a substantial unsupported
stretch of wire screen ‘occurs between the rolls
‘vibrations, which are imparted to the screen
of wire over the gap. The vibration of this
70 stretch sets up a train of standing waves in the
watery upper layer of the stock on the wire.
The resultingvagitation of the stock has the effect
of uniformly distributing the individual ?bers
through the upper layer of the stock immediately
imparting rapid vertical vibrations of small
amplitude to the side rails of the machine during 70
such operation.
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