Machine for the Manufacture of Hollow Articles of Fibrous Material, such as Wood Pulp and the like.
Year: 1892

page_text: COMPLETE SPECIFICATION.
Machine for the Manufacture of Hollow Articles of Fibrous Material,
such as Wood Pulp and the like.
I, CARL CHRISTENSEN of 1 Stenersgade, Christiania Norway Merchant 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:-
In the machines heretofore mostly used for the manufacture of pails and similar
articles from wood pulp, generally a hood of india rubber has been employed,
between which and a rigid perforated form or mould the pulp is pressed by means
of hydraulic pressure against the outer side of the elastic hood, the moisture of the
pulp escaping through the holes or pores in the rigid form. A great drawback
with this arrangement has been found therein, that the article to be pressed must
be given much thicker walls than necessary for the strength and practical purposes
of the same, for the reason that the walls get uneven outer surfaces and not the
same thickness all over, and the articles therefore have to be turned and finished
by means of mechanical implements. In this manner not only quite a great deal of
pulp is lost but there are also difficulties connected with performing the turning
and finishing oparations, for the reason that the peculiarities of the material
employed necessitates the use of tools specially constructed for the purpose.
To avoid the necessity for this difficult and ineconomical finishing of the pressed
articles is the purpose of this invention according to which the articles are at once given
the necessary thickness of walls and an even surface. This is attained by using instead
of the said elastic hood as outside mould, a greater or less number of rigid pistons or
stamps, working in chambers, in which the same fit exactly and arranged around
the inside rigid mould in such a manner, that the pistons, when in their innermost
position, together form the outside surface of the article. By using such moveable
pistons or sectional moulds another advantage is also gained, which consists therein
that also these outer moulds may be made perforated, so that the moisture in the
pulp can escape to both sides, this being of very great importance for obtaining a
first class and uniform product and for a quick performing of the pressing
operation.
In the accompanying drawing Figures 1 and 2 illustrate the invention
diagramatically. Figure 1 is a horizontal and Figure 2 a vertical section.
D designates the frame of the machine, which is at the same time utilized as
guides for the stamps by means of which the moulding of the articles is performed,
and the frame may therefore preferably be put together in such a way that it may
be employed for several sizes and shapes of objects to be formed. As shown there
are 3 stamps A¹, A" A for the sidewalls of the object; there may also be used
4 or a greater number of stamps but the number may only in exceptional cases be
reduced to 2 (for instance when the object has a square shape in which case the
stamps may be made angular, each comprising two sidewalls) the stamps are shown
perforated so that the water can escape through them as well as through the inner

page_text: mould B which latter may be arranged as usual on a board C. The perforations
may also be left out either in the stamps or in the inner form B.
The stamps may on their inner side be covered with rubber or with brass wire
cloth or similar substances. The shape of the same in the direction of their move-
ment varies according to the shape of the objects and is for pails that of a trapeze
the shape of the stamp A is the same as that of the bottom of the object and in the
example shown it is round, from which reason also the guide of the same is a
cylinder.
The stamps may be moved inwards against the mould B through any known
mechanical means. The stamps may be moved by hydraulic force, and for this
purpose the rods G₁ G" and G may be connected with the pistons of hydraulic
cylinders or the hydraulic force may be applied directly against the stamps, or
screws or excentrics may be used. As to the inlet for the pulp, this may be
arranged in any suitable way. It may for instance be arranged at the corners O
between the stamps. The stamps A A'A" A¹" are arranged in such a way that
they can go back a certain distance according to the quantity of pulp, to be
pumped in, in order to obtain the required thickness of the walls. In the guides of
the stamps there may for this purpose be arranged adjustable stops, by which the
stamps are stopped, when they are pressed outwards by the pulp.
A suitable construction of press furnished with this kind of outer mould is shown
in Figures 3-6, in which Figure 3 is vertical section, Figure 4 ground plan,
partially in section, Figure section through a-y Figure 4 and Figure 6 is a
detail to enlarged scale. The elevating mechanism for the inner form is not shown
in the drawing.
The inner form B is mounted on the board C, the edge of which may be held
tight against the edge of the frame D by suitable means in the usual or in other
ways. Around the frame D there are arranged four hydraulic cylinders E¹ El E
and E which by pipes el ell ell and e¹ are connected with a similar cylinder E,
arranged above the frame. The lateral cylinders are all of similar construction
and have each a piston F¹, whose rod G carries the stamp A', on which the
perforated form plate a' is mounted (Figure 4). At the back of it there are a
number of channels through which the water coming through the holes runs
away. The form plates and stamps are trapeze shaped and move in guides or
chambers of the same shape fitting closely in the same (Figure 5). The upper
hydraulic cylinder E, in which the piston moves is closed at both ends, so that
the piston may be worked in both directions; the mould stamp A for the bottom
of the object to be pressed is connected to this piston F by means of a hollow
piston-rod G; the mould plate a is arranged in a similar manner as the lateral ones,
but is preferably not perforated or porous. The hollow piston rod is used for
introduction of pulp from above. The channel in the piston rod is at its lower end
shut off by means of a valve c, the spindle of which is surrounded by the spring f
in such a way that the valve opens automatically when pressure is exerted from
above.
The lateral pistons are connected with the upper piston through a system of
levers and links g, h, i, k,l hanging in a cross-piece m fixed to the piston rod G.
By this arrangement all of the pistons are forced to move simultaneously forwards,
so that the thickness of the walls will be the same on all sides, and also that the
lateral pistons may be moved to their outmost position by means of the double
acting upper cylinder.
As will be easily understood the construction of the machine may in several
respects be varied without departing from the main principle of the invention,
consisting in moulds moving radially around the central mould in closely fitting
chambers.
Having now particularly described the nature of my said invention and in what
manner the same is to be performed I declare that what I claim is:
1. In presses for the manufacture of hollow articles of fibrous material the

page_text: combination with an inner form of outer piston like mould sections arranged radially
and movable relatively to the said inner form in such a way that when in their
innermost position they together form the outer surfaces for the object to be
pressed, while in their outermost position they form one wall of a set of chambers,
in which the pulp is pumped in, the side walls as well as upper and lower walls of
said chambers serving as watertight guides for the mould sections which are
moved inwards simultaneously and at the same rate by any suitable means.
2. In presses for the manufacture of hollow articles of fibrous material the use of
two or more hydraulic cylinders E' E" having pistons which are connected with
the outer mould sections A' A¹¹ in combination with a hydraulic cylinder E having
a piston which is connected with the mould section for forming the bottom of the
object to be pressed.
3. In presses for the manufacture of hollow articles of fibrous material the use of
a system of levers and links between the lateral piston rods and the upper piston
rod for the purpose of ensuring the simultaneous movement of all mould sections
towards the inner form, substantially as described and shown.
4. A press for the manufacture of hollow articles of fibrous material constructed
substantially as described and shown.
5. In presses for the manufacture of hollow articles of fibrous material the use of
mould sections such as A¹ having a perforated form plate a¹ and channel b' substan-
tially as described and shown.
ሰ
1000
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.