Improvements in or relating to Apparatus for Impregnating and Dyeing Wood.
Year: 1898

page_text: Date of Application, 23rd Már., 1898-Accepted, 20th May, 1898
COMPLETE SPECIFICATION.
Improvements in or relating to Apparatus for Impregnating and
Dyeing Wood.
I, GEORG FRIEDRICH LEBIODA, of 50, Rue St. Didier, Paris, in the Republic of France,
Manufacturer, do hereby declare the nature of this invention and in what manner
the same is to be performed, to be particularly described and ascertained in and
by the following statement:-
This invention relates to an apparatus for impregnating and dyeing or colouring
wood, a suitable fluid being passed under a high pressure longitudinally through the
fibres of the wood in the manner of filtration and in a constant stream. The said
liquid may be a dye stuff or may contain adhesive substances such as albumen, gum
and resin. Certain oils, metallic salts, antiseptic or decomposition preventing liquids
may also be employed.
The improved apparatus consists of a cylinder open below and closed above and a
cylinder closed below by a sieve or straining plate, which latter cylinder is directly
attached to the upper one by means of flange rings or the like. In this cylinder or
receptacle the wood to be treated is placed after having been first cut with a smooth
surface so as to stand level on the sieve plate. The holes left free by the wood in the
sieve plate are stopped with plugs and a thin layer of some suitable substance which
hardens when cold is poured over it. The liquid is finally conveyed under high
pressure into the receptacle and forced through the wood to be treated, after which
the liquid after depositing the dye or impregnating substances in the fibres of the
wood is discharged through the sieve holes under the lower part of the wood.
The improved apparatus is so arranged that the vessel receiving the wood may be
closed below by an under piece and be open above in order to force the liquid upward
through the wood from below if desired.
The under part is adjustable in height by means of a screw spindle and during the
impregnation from above is so far lowered that the workman can see the discharge of
the liquid through the sieve plate. The underneath vessel also serves as a receiver for
the liquid which may then be carried off by means of a discharge or catch pipe.
In proximity to the sieve plate the wall of the lower cylinder is further provided
with a hollow space in which after the completion of treatment of the wood, steam
may be admitted in order to soften the substance employed for closing the holes in the
sieve which are not covered by the wood and for fixing the wood.
This improved apparatus is shown in the accompanying drawings, in which,
Figure 1 is a vertical section ;
Figure 2, a horizontal section on the line x-x of Figure 1;
Figure 3, a section on the line y-y of Figure 2;
Figure 4, a section on the line z-z of Figure 2.
The vessel intended to receive the wood to be treated consists of an upper cylinder a
and an under cylinder b in which a bottom plate d provided with a flanged ring c and
having numerous holes is inserted from below. The two cylinders a and b are con-
nected by flange rings e and e¹ and bolts f. The lower cylinder 6 has an internal iron
casing 6 and is carried by three supports or standards g. The bottom plate d is
secured to the lower ring flange of the cylinder 6 by means of screw bolts h. Washer
rings are provided between the cylinders b and a and between the cylinder b and the
i

page_text: sieve plate d which produces a tight joint even under high pressure. The cylinder a
is closed above by means of a collar a' in which a manhole closed by a cover m and
carrying rings o are provided. The cylinder a has also a safety valve and a mano-
meter. An additional part p is arranged under the perforated bottom plate a which
part may be suitably adjusted vertically by means of a screw spindle p¹ and is revoluble
in a support p3 by means of a revoluble handwheel p². The flat edge of the part p engages
with an annular groove over an annular projection of the bottom plate d¹. Between both
plates a washer ring is arranged and compressed when the lower nuts h¹ of the bolt
h are tightened. A discharge opening q provided with a discharge pipe g¹ which is
capable of being closed is arranged in the under part p. A funnel q² attached to a
discharge pipe q³ is arranged beneath the opening q through which pipe the liquid can
be discharged when the pipe q¹ is opened. A tap or cock r, Figure 3, is inserted in
the cylinder b through which liquid under pressure can be pumped or forced into the
interior of the cylinders a and b. A tap 8 on the bottom plate d is also provided through
which liquid under pressure can be pumped under the bottom plate.
In order to be able to discharge if desired the liquid contained in the receptacles,
the cylinder b is also provided with a discharge tap u. The flange ring c of the bottom
plate d is also provided with a broad annular groove or channel in which steam may be
admitted through a tap t, Figure 4, as will be hereinafter described. Another tap t²
serves for letting off the steam and the liquid condensed therefrom, and a further
tap is inserted in the bottom plate d itself, Figure 4, in order to allow steam to be
conveyed under the sieve plate even when the under part p is pushed up in
its highest position.
The mode of working of the apparatus herein before described is as follows:-
The screws or bolts are slackened and the upper cylinder a is raised by means of
the lifting rings o from off the lower cylinder b. The under part p is then brought
into its lower position by means of the hand wheel p². The wood A to be treated,
which is cut smooth on its faces, is placed on the sieve plate d and the holes in the
bottom plate which remain uncovered by the wood are closed by means of wooden
plugs. A cement or substance such as resin or tar capable of being melted is then
poured between the pieces of wood and the inner wall of the cylinder. On this sub-
stance setting, a cement like layer a few centimetres in height forms a tight joint or
closing to the lower part of the cylinder and the said layer also serves to keep the
wood in position. The cylinder a is then again brought into its position and screwed
tight by means of the bolts f, a good joint being obtained by reason of the washer
rings employed.
The liquid under pressure is then allowed to enter the receptacle through the tap r,
which liquid only finds an exit through the wood and the holes beneath the same.
The sap is thus expelled from the wood and the liquid under pressure takes its place.
As the under part p is lower than the cylinders the discharge of the sap and the
liquid under pressure through the holes in the bottom plate may be readily
observed. After the liquid has penetrated every fibre of the wood along its entire
length a first time, it may be caught on its discharge from the openings of the
plate d in the lower part p and by opening the pipe q¹ carried off through the pipe q³
in order to be forced through the wood for a suitable second treatment.
In case the liquid under pressure has to be discharged from the wood receptacle
without passing through the sieve plate and part p the tap u is opened.
After the liquid under pressure has acted sufficiently from above it is allowed to
pass from below under the bottom plate d. To enable this to be done the under
part p is raised by means of the hand wheel på and fastened by means of the
nuts h¹ of the bolts h whilst the washer ring is compressed. The tube or
nozzle q is then tightly closed and the manhole cover removed. The tap is now
opened and the liquid under pressure passes under the bottom plate, and penetrates
from below upwards through the wood. When the impregnation is completed the
liquid is allowed to run off and steam is conveyed through the taps t and t¹ into
the annular channel round the flanged ring c as well as under the bottom plate d,
whereby the layer of cement, resin or the like employed for closing the holes not

page_text: The
covered or closed by the wood and for holding the wood in position is softened.
upper cylinder is then lifted and the finished wood removed in order to be replaced
by a fresh supply, after which the process herein before described is repeated.
This invention is of great advantage in that the impregnation takes place in the
direction of the fibres and the pressure may be allowed to rise up to a certain degree
which can be easily and exactly ascertained by means of the manometer. A further
advantage is that no special form need to be given to the wood and the colouring of
the wood by impregnation by a cold process may take place so that the fibres of the
wood are not in any way effected. Finally by the present invention timber, such for
instance as railway sleepers, may be so thoroughly impregnated with a decay resisting
substance that it cannot decay and thereby very great durability is imparted
to it.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what I
claim is :-
1. An apparatus for impregnating wood after the manner of filtration, consisting of
a vessel closed above and having below a perforated bottom plate substantially as set
forth.
2. In apparatus for impregnating wood, means for closing the holes in the bottom
plate not closed or covered by the wood to be treated, and surrounding the wood with
a thin layer of a suitable substance which hardens when cold, substantially as
herein before described.
3. In apparatus for impregnating wood an under part capable of being vertically
adjusted and serving for catching the liquid flowing through the bottom plate, said
under part being connected with a tight joint to the bottom plate when the
impregnation is to take place from below upwards after the removal of the manhole
cover, substantially as herein before described and shown in the accompanying
drawings.
4. In apparatus for impregnating wood, the arrangement of an annular channel in
the annular flange of the bottom plate in which steam is admitted under the said
bottom plate after the under part has been raised, in order to soften or melt the layer
of covering material which has set on the said bottom plate, after the treatment has
been completed, şubstantially as herein before described.
Dated this 22nd day of March 1898.