Year: 1887

page_text: Date of Application, 29th June, 1887
Complete Left, 18th Feb., 1888
Complete Accepted, 20th Apr., 1888
1, JOSEF GAWRON, of Grabow near Stettin, in the Empire or Germany do hereby
declare the nature of this invention to be as follows :-
This invention relates to friction-couplings having an engaging and disengaging
device.
The said invention comprises-the-nave which is secured to the driving shaft and
has two side walls between which all the plates are pressed together by screws
according to the power to be transmitted. The said plates are adapted to be displaced
in the direction of the axis of the shaft upon the nave which is provided with guides
or feathers.
The intermediate plates are loose upon the nave and have at their circumference,
formed by curves, two teeth each. The casing together with a fixed pulley turns
loosely upon the driving shaft the said casing enclosing the plates.
On the pawl carrier shafts which are firmly screwed to the casing are pivotted
toothed pawls with which, by means of adjusting screws any desired number of plates
can be firmly connected with the casing, thereby attaining the advantage that any
portion of the power once produced can be transmitted. The tappet shafts with
the disengaging arms are pivotted in the casing and firmly connected with the
disengaging tappets.
Each of the toothed pawls are acted upon by springs. The disengager is loose upon
the driving shaft and can be displaced by an operating lever, only in the direction of
the axis of the shaft.
When the coupling is engaged, the disengaging arms slide upon the cylindrical
projection of the disengager, the latter forming an elliptical curve the minor axis of
which coincides with a cylindrical portion of the disengager. When it is desired to
disengage the coupling, the operating lever must be moved toward the casing; the
disengaging arms are thereby lifted from the elliptical curve on to the cylindrical
portion and slide upon
the same, whilst the disengaging tappet brings the pawls out
of engagement with the teeth of the plates, the coupling is now disengaged. The
disengaging arms are kept together by springs.

page_text: When it is desired to engage the coupling, the disengaging lever is moved in
the opposite direction.
The coupling may be simplified if all the plates are always intended to engage at
the same time with the toothed pawls, and are thus firmly connected with the casing.
In order to achieve this, the following modifications must be made in the coupling
above described.
The tappet shafts with the disengaging täppets and the springs which act upon the
toothed pawls are entirely dispensed with.
The plates are connected by guide bolts in such a manner that they can be displaced
in the direction of the axis of the shaft, but remaining loose, thus combined and
capable of turning upon the nave. The pawl carrier shafts are directly provided with
the disengaging arms and firmly connected with the toothed pawls. The disengager
remains the same, and the disengaging arms are again kept together by springs.
The casing of the coupling can be driven as well as the driver.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.

page_text: Couplings.
I, JOSEF GAWRON, of Grabow near Stettin, Germany, 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 :-
My invention relates to friction-couplings serving to transmit power from one
rotative piece of machinery to another, and its object is to provide new and efficient
means whereby the said power may be limited to a definite predetermined amount,
or to a part of the amount for which the coupling has been constructed and
regulated.
For this purpose the coupling is composed of a number of juxtaposed plates or
disks pressed by screws into frictional contact with each other, the said plates being
connected alternately by means of feathers, or the like, to the shaft that carries the
coupling, and by means of pawls to a casing enclosing the plates, and which is loose
on the shaft. The amount of power which can thus be transmitted from the shaft to
the casing, or vice-versa, is consequently dependent upon the amount of friction pro-
duced by the variable pressure of the plates upon each other, and besides, the said
amount of power may be reduced by bringing one or more of the said pawls out of
engagement with the corresponding plates.
On the annexed sheet of drawings Fig. 1 represents in longitudinal section a
coupling constructed according to my invention. Fig. 2 is a transverse section
thereof on line A B, Fig. 1, together with some parts:(shown in dotted lines) which
adapt the coupling to serve as brake. Fig. 3 is an outside view, with section on line
CD, Fig. 1, of a coupling combined with other means for adapting the same to be
used as brake. Figs. 4 and 5 are outside views involving a modification of the
coupling. Figs. 6, 7 and 8 show parts of the coupling in detail, Figs. 6 and 7 being
drawn to a larger scale.
In Figs. 1 and 2, d and g are the plates by the reciprocal frictional contact
whereof the power is transmitted. These plates are placed upon a nave f secured to
the shaft C, the plates y being connected to the nave by feathers so that they will
rotate therewith, while they are capable of being moved on the same lengthwise.
The plates d are loose on the nave. The said nave has a side-wall or flange ",
against which the plates d and g are pressed by screws o, working in holes of a flange
at the opposite end of the nave. In order to attain an elastic pressure, springs 8 are
inserted between the flange " and the contiguous plate, or pieces of india rubber
are placed under the screws o. The plates and the nave are enclosed in a casing a
arranged to turn loosely on the shaft C, and which carries a pulley, a toothed wheel or
the like (not shown in the drawing). The plates & have on their circumference
ratchet-teeth, and within the casing are disposed opposite to the plates d the pawls s
pivoting on screw-bolts T, which pass through the casing. The said pawls are pressed
towards the plates d by springs i, so that when they are free to yield to the force of
these springs, they will come in engagement with the teeth of the plates d. If all

page_text: the pawls are in engagement with the said plates, the amount of power. that can be
transmitted by means of the coupling depends upon the sum of the frictional
resistances between the surfaces of the plates d and y, and is thus in proportion to
the number of pairs of plates in operation, the plates slipping upon each other as
soon as a certain power is exceeded. In any given coupling the said amount of
power may consequently be reduced by putting one or more of the plates & out of
operation and allowing it to be carried round by the neighbouring plates g. For this
purpose the coupling is provided with screws passing through the periphery of the
casing and adapted to press against tails on the pawls s, so as to permanently lift
the latter clear of the teeth of the plates d. In proportion to the number of pawls
that are thus lifted and put out of action, the maximum amount of power that can be
transmitted by the coupling is reduced.-
:
In view of allowing the whole coupling to be engaged and disengaged at will,
means are provided for, whereby all the pawls may be disconnected from the plates
at once. These consist in tappets t, fixed to axles v passing through the casing and
carrying on the outside of the latter the respective arms and w, or disengaging-
arms, whereby the axles may be turned and the tappets caused to lift the pawls. The
said arms are connected together by springs, tending to draw them towards each
other, and to keep the tappets down but the arms may be brought farther apart by
means of a disengager 1 m q, consisting in a boss placed on the shaft C, the portions
and y
of the same being cylindrical, but of different diameter, while the intermediate
portion m is formed according to an elliptical curve the respective axes whereof are
equal to the diameters of the portions and q. When this boss or disengager is in
the position shown in the drawing, the portion 7 is between the arms w w¹, and these
are at the smallest distance from each other; but, when the disengager is pushed
towards the coupling by means of the lever n, arranged for this purpose, the coupling
being at the time in rotation, the portion m, on passing in between the arins, will
force them away from each other, and finally the portion 9 slipping between the arms,
will keep them asunder. By this motion of the arms the tappets t are caused to bring
the pawls out of engagement with the teeth of the plates d, the coupling being then
disengaged. When it is desired to engage the coupling, the lever n is moved in the
opposite direction.
.
In order that the pawls s, on being released by the tappets t, may always come
fully in engagement with the teeth of the plates d, the following arrangement has
been made. To a projection on the side of each of the said plates is fixed a spring,
Figs. 1, 2, 6, 7, which in its normal state bears with its free end against the corre-
sponding lateral surface of the plate, as shown by the right hand portion of Fig.47,
and the outer edge whereof forins a curve running from a point of the periphery
of the plate to the outer edge of the tooth being rearward of the said point, relatively
to the direction of motion of the plate. Moreover, each pawl is made, on the side
towards the springs a, by so much broader than the plate that, if the pawl, on being
released by its tappet t, should drop upon the spring, the latter will prevent the pawl
from engaging with the tooth and conduct it away over the same. If, however, the
pawl, when released, drops forward of the spring upon the edge of the plate, the
spring during its motion with the plate, will touch laterally against the pawl and be
bent away by the same from the plate, the pawl then coming by its shoulder in full
engagement with the tooth, as shown in the left-hand portion of Fig. 7.
it
If the coupling is designed to be employed for always transmitting the same power,
may be simplified in the following manner. The tappet-shafts with the disen-
gaging-tappets t, and the springs i which act upon the pawls s, are dispensed with.
The plates d are connected together by bolts y, Fig. 2, in such manner that they
remain movable in the direction of the axis of the shaft and capable of turning on
the nave. The pawls & and the disengaging-arms w w¹ are fixed to the axles r,
which are arranged to turn in the holes of the casing through which they pass. The
disengager remains the same and the disengaging-arms are again drawn towards
each other by springs. With this arrangement the plates d will always be all
connected with the casing a or disconnected therefrom.
:

page_text: It is evident that by means of the coupling motion may be transmitted as well
from the shaft ( to the casing a, as from the casing to the shaft.
The coupling may also be used as brake. If it is to serve for this purpose only,
the casing a is made a fixture, for instance by fastening it by stays 1, such as are
shown in Fig. 2 by dotted lines, to the ceiling E or any other stationary part. If
the coupling is to be employed as brake in addition to its serving as power-trans-
mitting apparatus, the arrangement represented by Fig. 3 is avaible. According to
the same the casing a is provided with two teeth 9, disposed to engage with the
teeth 10 of the hars 2, suspended to the ceiling E, the said bars being connected by
links 3 to a bar 4 sliding in guides, so that when the bar 4 is pulled down, the
teeth 9 and 10 engaging with each other, will stop the rotation of the casing,
whereas when the bar is pushed upward, the casing will be free to rotate.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:
1. In a friction-coupling, the combination together of the nave / having a flange,
the plates g connected to the nave so as to rotate therewith, the plates d alternating
with the plates g and having ratchet-teeth and placed loosely on the nave, screws o
for pressing the plates d and g together and against the flange, the casing a rotative
independently of the nave, the pawls s pivoted within the casing a and adapted to
be engaged with the teeth of the plates d by means of springs, substantially as and
for the purpose described.
2. The combination, with the friction-coupling as herein before claimed, of the
screws whereby the pawls can be individually prevented from engaging with
the ratchet-teeth of the plates d, substantially as and for the purpose specified.
3. The combination, with the friction-coupling as set forth in claim No. 1, of the
axles v with tappets t, the disengaging-arms w w¹ fixed to the axles and connected
together by springs, and the disengager 1 mq, substantially as and for the purpose
specified.
4. In the friction-coupling set forth in claim No. 1, the combination, with the
plates d, of the springs fixed thereto, the pawls s being arranged to project over
the side of the plates d towards the springs a, substantially as and for the purpose
described.