Improvements in Bearings for Sieves and Strainers of Paper-making Machines.
Year: 1898

page_text: Date of Application, 10th May, 1898-Accepted, 11th June, 1898
COMPLETE SPECIFICATION.
Improvements in Bearings for Sieves and Strainers of Paper-making
Machines.
I, WALTHER HELLER, of Cöthen, in the Duchy of Anhalt, German Empire,
Engineer, 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 the bearings of sieves and strainers of paper-making
machines, and has for its object various improvements in the construction of the
same, more especially relative to the employment of ball bearings.
In sieves and strainers hitherto in use, the sifting-table, or more precisely, the
sieve-portion of same, was caused to travel (by the action of the agitating
mechanism), firstly either along a circular path or to be moved along in a hori-
zontal direction. Besides this a combined cross and longitudinal movement of
the sieve is known and has been employed, but also herein the sieve table can
execute a movement in a vertical plane.
In the first case the weight of the sifting-table had to be overcome, and although
by the alteration of the movement to a horizontal one, this disadvantage was
overcome, yet, for the reason, that the sifting-table moved simply to and fro, i.e.
returned in the same direction as the forward movement, and thus performed a
movement in the parallel direction to the longitudinal axis of the paper, the felt-
ing of the paper was nevertheless by this construction only effected in the direc-
tion of the longitudinal axis, so that machine-made paper had not the quality of
hand-made paper, as in this latter case the operator could mix the latter in any
required, or in different directions.
A better felting of the paper was no doubt produced by the third hereinbefore
mentioned movement of the sieve, (viz. the combined longitudinal and cross move-
ment), but here the disadvantage existed, that an energetic and rapid agitating
of the sieve parts was virtually impossible, as, to effect or bring about such a
movement, firstly two independently operating agitating or shaking operations
are necessary; secondly, the massive machine parts comprising the frame bear-
ings, bottom and couching press must in such a case also be caused simultaneously
to execute the required movement with the sieve portion, for which convenient
movement these machine parts are (as is at once apparent) much too heavy;:
lastly the objection to this combined longitudinal and cross movement exists,
that in the same, the sieve table must also perform a swinging movement in a
vertical plane which has proved to be very disadvantageous in practice.
The present invention has the object of removing these disadvantages in such
manner, that the sifting portion of the machine no longer performs a to-and-fro-
movement, but travels in a closed path, or more precisely the sieve forms as it
were an endless band and by these means a felting of the paper is attained which
equals that of hand made paper. It is also simultaneously attained that the paper
pulp is prevented from collecting at the ends of the sieve and becoming blocked

page_text: at these points, the result of such blocking clearly being, that the paper pulp
cannot be evenly or equally distributed, as when more pulp remains at the ends
of the sieve in consequence of an inefficient operation of the machine, it is clear
that a paper of unequal thickness must be produced.
To obviate these drawbacks and to ensure, that the sifting portion of the table
should perform as it were a closed or endless. path, it has been found necessary
in the present invention to deviate from the known methods of journalling the
sifting table.
In the construction's hitherto mentioned the "sifting tables' were either hinged to
the supporting columns to effect a vertical movement, or, when this movement was
in a horizontal direction, the table was, pivoted to, a fixed point and moved upon
rollers, the longitudinal axis of which was parallel to the axis of the table.
31° Furthermore, in, the known constructions, the circular movement of the sift-
ing-table around its point of rotation produced not only the rolling movement,
(caused by the action of the rollers), but there was also a sliding movement viz.
in the direction of the longitudinal axis of the rollers. For this reason these con-
structions could not be employed where the sifting table was required to traverse
a closed path..
Proceeding now to describe more particularly my improvements in question,
I refer to the accompanying drawings, in which similar letters denote similar
parts throughout the several views, and in which:
Figure 1, shows a side-elevation, .
Figure 2, an end-view,
Figure 3, is a plan of a sifting apparatus, and
Figures 4, and 5, show the movement of the table in two forms of construction.
In the drawings the sifting table A (Figure 1) resting upon balls a is movably
journalled in oil-troughs of the supporting columns S¹.
So..
The sifting table A does not revolve round a fixed point but the same performs
or traverses, as shown in Figures 4 and 5, a path closing in itself, which path
may, as shown in Figure 4, either be circular, or, as shown in Figure 5, may take
the form of an ellipse.
An example of one of the most suitable methods or mechanism by means of
which this movement can be attained, is shown in the accompanying drawing in
which the eccentric E (Figures 2 and 3) actuates the part B of the sifting table,
the said eccentric being located upon an upright shaft w¹ and driven by the
shaft w actuated by the conical wheels C. It will be seen from this example,
that according to the position of the eccentric E to the sifting table A that the
latter is either actuated in the manner shown in Figure 4, or in the manner shown
in Figure 5. In both cases the movement gradually decreases to approximately
null in the cross direction to the longitudinal axis of the table, and opposite to
the point (Figure 4), at which the movement started, so that at the opposite
end (y) only a movement of the table in the longitudinal direction can take place.
This decreasing movement is clearly indicated in Figures 4 and 5. Furthermore,
as shown in Figure 1 (by a side-view), the balls of the journal or bearing are so
fitted, that they do not permit of a lateral deviation or movement.
It is, however, also possible to effect the same movements at different portions
of the sifting-table when for instance, the eccentric E is caused to come into
engagement at the centre of the table, or, when at both ends of the table two
driving gears are, simultaneously employed.
Instead of the method of actuating the sieves, as shown in the drawing, any.
other suitable means may be employed, which permits of the sifting table, or,
more precisely, of the sifter or strainer traversing a closed or endless path.
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
1 claim is:-
1
A ball bearing device for the sifting or straining tables of paper-making

page_text: machines, characterised by the employment of balls (a), arranged in the oil
troughs (k) of the supporting columns (S¹ S6) of the frame of the machine, upon
which balls (a), the sifting or straining table can roll, without sliding, and can
traverse a path in a horizontal plane, said traversed path returning in itself; all
for the purpose of obtaining a felting, equal to the felting of hand-made paper,
substantially as described.