Year: 1888

page_text: I, OTTO BRAUN, Doctor of Philosophy, of Berlin, in the Empire of Germany Civil
Engineer, do hereby declare the nature of this invention to be as follows:-
The balance regulators employed heretofore in centrifugal machines with elastically
journalled axle fulfil the purpose of displacing the centre of gravity of the drum or
cylinder into the axis of revolution, but they can but seldom distribute the mass of
the cylinder in such a manner that the plane, to which the drum has the greatest
momentum of inertia, is perpendicular to the axis of revolution.
For this reason the work of the centrifugal cylinders elastically lodged has hitherto
not been quite satisfactory; since the centrifugal force tends to direct equatorially the
plane of inertia and encounters at the fastenings between axle and cylinder a
resistance changing with the speed of revolution. The vertical component of the
directing force acts downwards, wearing the foot bearing and shaking the support.
In the present invention this drawback is obviated by suspending the cylinder by
means of a universal joint arranged above the centre of gravity of the empty cylinder
on an axle lodged elastically in any suitable manner.
The bearing is not secured on the axle, but only pressed onto the same by the
weight of the cylinder. As a support for the bearing a ring is secured on the axle
and a leather disc lies between the ring and bearing.
In order to prevent the draught of the belt from deflecting the elastically lodged
axle from its vertical position, the axle is divided into two parts, viz. an upper axle
journalled elastically in a spring bearing in any suitable manner and the lower axle
journalled so as to be stationary. The upper axle bears with its lower end on the
head of the lower axle in yielding connection by means of a caoutchouc ring fixed
rigidly onto the conical upper end of the lower axle.
The upper axle is thereby allowed to oscillate to such an extent, that the centre of
gravity of the cylinder falls into the elongation of the axis of the lower axle. The
latter carries a pulley and is actuated by a single endless cord from a suitable pulley,
the cord being wound several times round the two cord pulleys. The last winding

page_text: running from the uppermost cord-groove of the one pulley is guided over a
roll, by which the cord is prevented from being confused or entangled and may be
stretched.
For instance a single cord quintuply wound has over five endless cords the
advantage of a uniform tension in all parts and it has over a single cord of quintuple
thickness the advantage, that pulleys of smaller diameter can be employed. With a
single multiply wound cord circumferential speed of the drum can be attained, which
is otherwise impossible.
For the purpose of ascertaining the speed of the drum, a small vertical glass tube is
placed above the universal joint on the head of the axle; this tube is partly filled with
a transparent liquid. The glass tube closed at both ends is graduated, and when it
revolves with the axle the liquid rises on the wall of the tube according to the speed
of revolution.
A similar device may also be arranged on the driving axle. From the difference
in the indications of the two tubes, the loss of revolution which has taken place in the
intermediate mechanism between the driving gear and the centrifugal drum can be
ascertained.
1
C
1000

page_text: I, OTTO BRAUN, Doctor of Philosophy, of Berlin in the Empire of Germany, Civil
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 centrifugal machines and consists in certain improvements
therein as hereinafter described and claimed.
The first improvement relates to the manner of mounting the drum or centrifugal
cylinder.
The balance regulators employed heretofore in centrifugal machines with elastically
journalled axle fulfil the purpose of displacing the centre of gravity of the druin or
cylinder into the axis of revolution, but they seldom distribute the mass of the drum
in such a manner that the plane to which the drum has the greatest momentum of
inertia is perpendicular to the axis of revolution.
The centrifugal force tending to direct the plane of inertia equatorially therefore
meets with a certain amount of resistance changing with the speed of revolution, and
the resultant of these forces acts downwards to the wearing of the foot bearing and
shaking of the support.
In the present invention this drawback is obviated by suspending the cylinder
upon or by means of an universal joint arranged above the centre of gravity of the
empty cylinder on an axle lodged elastically in any suitable manner.
A further improvement relates to the driving of the axle of the cylinder, its object
being to prevent slipping of the belt or cord, to decrease the wear of the same and,
generally, to improve the driving.
A further in.provement consists in a gauge for ascertaining the speed of revolution.
Reference being made to the drawings accompanying this specification.
Fig. 1 is a vertical central section of the improved machine. Fig. 2 is a plan view
thereof with drum and bearings removed. Fig. 3 is an horizontal section of the drum
and its universal joint. Fig. 4 is a section of the drum axle below the drum. Figs. 5
and 6 are respectively elevation and plan of a modified form of driving gear.
Fig. 7 is a side elevation, Fig. 8 an end elevation and Fig. 9 a plan view of another
modified form of driving gear. Fig. 10 is a detail view of a part of the last mentioned
gear on an enlarged scale.
The universal joint for the drum is preferably composed of the four pivotal
pins 3 and the three concentric rings f. m. and g of which the last may be
rigidly fastened to or formi part with the druin. The inner ring f. encircles the bead
of the axle being loosely fitted thereon and resting on a flange or collar r, a leather
or like disc or washer L being placed between the ring f and the collar so that
the friction may be less at this joint than at any other part of the gear and conse-
quently permit of the slipping of the drum which is unavoidable on starting the
machine or changing the speed.

page_text: In order to prevent the lateral pressure of the driving belt from deflecting the axle
in its elastic bearings from its vertical position, the axle is divided into two parts,
namely an upper part O journalled in a collar elastically supported by the spring p
or in any other suitably elastic manner, and a lower part u supported in stationary
bearings. A friction joint is made between the parts O and u, the part O being
conically recessed at its lower end to rest upon a corresponding conical nose on the
upper end of the part u. A rubber cap K is placed between the parts being preferably
fixed rigidly on the nose of the part u. The rubber cap therefore forms a sufficiently
secure connection permitting of the oscillation of the shaft without material dis-
placement. The cap K and spring p are intended to permit the shaft o to oscillate
sufficiently to bring the centre of gravity of the drum into the line of the axis of the
part u.
The driving gear may be constructed as follows; On the shaft u is a pulleys of
small diameter but preferably provided with several grooves, parallel with the shaft u
is journalled a shaft driven by power in any suitable manner and carrying the pulley S
of comparatively large diameter; intermediate between the pulleys sand S is
journalled a small tension or guide pulley N. An endless belt or cord is wound
about the pulleys s and S preferably five or six times. Where the said cord passes up
from the lowest groove of one pulley to the highest groove on the other, it is passed
round the guide pulley N (see fig 2) both for the tensioning of the cord and for
holding it from contact with the other parts of the cord. Or in place of passing the
cord an equal number of times round each pulleys and S it may be passed once
round the pulley N in the manner shown in Figs. 5 and 6.
The driving gear may likewise be modified as shown in Figs. 7 to 10, in which the
pulley Sis made larger with but one groove and for convenience journalled to revolve
in a vertical plane. The guide pulley e carries off the cord and guides it as shown
preferably so that the cord lies in contact with but little more than three fourths of
the circumference of the pulley S. The cord passing round the upper groove a of the
pulleys (Fig. 10) passes round the guide and tension pulley n and thence back round
the lower groove of the pulleys to the pulley S.
According to the position of the pulley n. The part of cord in contact with the
groove a may extend along more or less than the half of the circumference of the groove,
the length however in contact with the groove will be to a corresponding degree less
or more than the half of the length of the circumference so that the total length of
cord in contact with pulley s is equal to a whole circumference. The frictional power
being in proportion to the fraction of circumference in contact, with the belt, it follows
that any slipping of the belt that may occur will happen on the circumference of the
pulleys so that wear on the belt is much lessened, and the driving more secure.
To ascertain the speed of the drum a small glass tube is vertically fixed above the
universal joint on the head of the axle O, this tube is partly filled with a transparent
liquid and is closed at both ends. When it revolves with the drum the liquid rises
within the wall of the tube to a height corresponding to the speed of revolution the
tube should be graduated to enable the height of the liquid and consequently the speed
to be ascertained. The tube could be graduated by experiment.
I prefer also to arrange a similar device on the driving shaft, so that the difference
in the indications of the two tubes may show the difference in the speed of revolution
of the driving shaft and of the drum, and conseque: tly the loss in the transmission of
power.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is ;-
In centrifugal machines-
1). The combination with the centrifugal drum, and elastically journaled shaft
supporting said drum; of an universal joint between said shaft and drum the centre of
gravity of the drum falling below the said universal joint, substantially as and for the
Buenos not fouth

page_text: 2). The combination with the centrifugal drum of an elastically journalled shaft O
carrying said drum, and a shaft u driven by power, journalled in stationary bearings
and supporting said shaft O substantially in the manner specified and for the purpose
set forth.
3). The combination with the shaft of a centrifugal drum, of a pulley with several
grooves on said shaft, a driving shaft, a pulley with several grooves on said driving
shaft, an endless belt or cord wound on said pulleys substantially as set forth.
4). The combination with the pulleys s and S; of the guide and tension pulley N
substantially as and for the purpose set forth.
"
5). The arrangement of the driving belt in such a manner that the fraction of the
circumference of the larger driving pulley in contact with the belt is less than that of
the circumference of the pulley on the centrifugal drum shaft in contact with said
belt.
6). As a speed indicator the tube graduated, and closed, and containing a certain
quantity of liquid; vertically fixed on the axis of rotation.
HERBERT & Co.,
18, Buckingham Street, Strand, London, W.C.,
Agents to Applicant.
HERBERT & Co.,
18, Buckingham Street, Strand, London, W.C.,
Agents to Applicant.