IMPROVEMENTS IN SELF ACTING BRAKE OR FRICTION COUPLINGS
Year: 1878

page_text: LETTERS PATENT to Eduard Becker, of Berlin, Germany, Mechanical Engineer,
for the Invention of "IMPROVEMENTS IN SELF ACTING BRAKE OR FRICTION
COUPLINGS."
Sealed the 21st March 1879, and dated the 29th November 1878.
PROVISIONAL SPECIFICATION left by the said Eduard Becker at the
Office of the Commissioners of Patents on the 29th November 1878.
EDUARD BECKER, of Berlin, Germany, Mechanical Engineer. "IMPROVEMENTS
IN SELF ACTING BRAKE OR FRICTION COUPLINGS."
The object of this Invention is to couple or connect and to disconnect without
any shock two shafts situated in the same axial line, and one of which is the driving
shaft, and that either during rest or during rotation of the driving shaft, or of both,
and by means of a new or improved brake appliance, all as hereinafter described.
The two shafts may in general abut against each other, or one may run partly
in a recess in the end of the other so long as the rotation axis of both be the
same.
The driving shaft is fitted with a loose lever or crank, the crank pin of which
forms the fulcrum for a block or cross piece, to which are directly or indirectly con-
nected the ends of a brake band, which passes round a brake drum fixed on the
driven shaft, or to which is directly or indirectly connected one or more brake
blocks (or the block or cross piece may itself form the brake block). The brake
band is tightened by means of a lever or crank, which is fastened on the driving
shaft, and the crank pin of which is connected to an arm on the aforesaid block, to
which the brake band is attached, so that this block when turned on its fulcrum
tightens the band on the brake drum.
When the friction between the brake drum and the band suffices for overcoming
the resistance of the driven shaft, this latter is carried round and turns in the same
direction and with the same speed as the driving shaft. The crank pin of the fixed

page_text: crank moves in a slot in the arm of the block for allowing both cranks to be
relatively changed in position.
This coupling may also be applied for coupling a driven strap, or other pulley or
wheel, or other revolving part, with its shaft or vice versa, or for coupling two
machines, also with especial advantage for working a winch or crane. The coupling
may be released by a special contrivance, consisting of a wedge piece entering
between back prolongations of the loose and the fixed crauk, such wedge being
operated say by a screw fitted with a friction wheel operated in one direction or the
other by contact with one of two lateral, not revolving, discs or rims.
When this Invention is applied to winches or cranes, or other hoisting or lowering
gear, I prefer to provide the loose crank with a ratchet wheel and pawl, whereby I
gain the peculiar advantage that the driving shaft or barrel with its winch handle
does not revolve during the descent of the load, thus preventing a great danger of
accidents to the labourer, and also that the load is braked into a state of rest when
the pawl is put in gear and the handle let go..
This Invention is also applicable for giving a shaft, varying speeds of rotation,
each of the driving pulleys being fitted with this brake coupling and the one for
transmission of the greatest speed with a disconnecting appliance.

page_text: SPECIFICATION' in pursuance of the conditions of the Letters Patent filed by
the said Eduard Becker in the Great Seal Patent Office on the 29th May
1879.
EDUARD BECKER, of Berlin, Germany, Mechanical Engineer.
IN SELF ACTING BRAKE OR FRICTION COUPLINGS."
"IMPROVEMENTS
The object of this Invention is to couple or connect and to disconnect without
any shock two shafts situated in the same axial line, and one of which is the
driving shaft, and that either during rest or during rotation of the driving shaft,
or of both, and by means of a new or improved brake appliance, all as hereinafter
described.
The two shafts may in general abut against each other, or one may run partly in
a recess in the end of the other so long as the rotation axis of both be the
same.
The driving shaft is fitted with a loose lever or crank, the crank pin of which
forms the fulcrum for a block or cross piece, to which are directly or indirectly con-
nected the ends of a brake band, which passes round a brake drum fixed on the
driven shaft, or to which is directly or indirectly connected one or more brake blocks
(or the block or cross piece may itself form the brake block); the brake band is
tightened by means of a lever or crank, which is fastened on the driving shaft, and
the crank pin of which is connected to an arm on the aforesaid block, to which the
brake band is attached, so that this block when turned on its fulcrum tightens the
band on the brake drum. When the friction between the brake drum and the band
suffices for overcoming the resistance of the driven shaft this latter.is carried round
and turns in the same direction and with the same speed as the driving shaft. The
crank pin of the fixed crank moves in a slot in the arm of the block for allowing
both cranks to be relatively changed in position..
This coupling may also be applied for coupling a driven strap or other pulley or
wheel, or other revolving part with its shaft, or vice versa, or for coupling two
The coupling
machines also with especial advantage for working a winch or crane.
may be released by a special contrivance consisting of a wedge piece entering
between back prolongations of the loose and the fixed crank, such wedge being
operated say by a screw fitted with a friction wheel operated in one direction or the
other by contact with one of two lateral, not revolving, discs or rims.
When this Invention is applied to winches or cranes, or other twisting or lowering
gear, I prefer to provide the loose crank with a ratchet wheel and pawl, whereby
gain the peculiar advantage that the driving shaft or barrel with its winch handle.
does not revolve during the descent of the load, thus preventing a great danger of
accident to the labourer, and also that the load is braked into a state of rest when
the pawl is put in gear and the handle let go.
This Invention is also applicable for giving a shaft varying speeds of rotation;
each of the driving pulleys being fitted with this brake coupling and the one for
transmission of the greatest speed with a disconnecting appliance.
.
Figure 1 of the accompanying Drawings is an end view and Figure 2 a vertical.
cross section of one arrangement.
The coupling or connecting is caused thereby, that the driving shaft a is fitted.
with a loose lever or crank b, the crank pin c of which forms the fulcrum for a
block or cross piece d, to which are attached the ends of a brake band d¹, which.
passes round a brake drum e fixed on the driven shaft f. The brake band d' is
tightened by means of a lever or crank g, which is fastened on the driving shaft a,
and the crank pin of which is connected to an arm on the aforesaid block d to.
which the brake band d' is attached, so that this block d when turned on its fulcrum
tightens the band on the brake drum e. When the friction between the brake
drum e and the band d¹ suffices for overcoming the resistance of the driven shaft f,.

page_text: this latter is carried round and turns in the same direction and with the same speed
as the driving shaft a.
This brake action and consequent coupling of the two shafts must take place each
time, because the crank b which carries the block d with the brake band d' is loose
on the driving shaft a, and is only carried along by the crank g, which is fast on
the same shaft. The crank pin of the fixed crank g moves in a slot in the
aforesaid arm of the block d, thereby allowing both cranks to be relatively changed
in position.
The coupling is released either when the driving shaft a relatively to the driven
shaft obtains a suddenly retarded or slight backward motion, or when the driven
shaft through some other power obtains a greater speed than it receives from the
driving shaft, or when through a special appliance both cranks are approached to
one another.
This coupling may advantageously be applied in a number of special cases, for
instance, for two pieces of shafting having the same axis, and of which one is the
driving shaft and the other is to rest at times, or for coupling a driven strap pulley
or pulley or tooth wheel with its shaft or vice versa, for coupling a driven shaft
with such a pulley or wheel, or for coupling two machines which have jointly to
accomplish a certain work, also with special advantages for working a winch or
crane. The coupling also admits of using a shaft with varying speed of rotation.
Figures 3 to 6 illustrate some examples of the application of this coupling.
Figures 3 and 4 represent the coupling of two shafts, of which a is the driving
and the driven shaft, also shewing as an example an apparatus for releasing the
closed coupling. The closing of the coupling will be clear from the foregoing and
from the Drawing. For releasing the coupling the two cranks b and g are in this
instance made to approach to one another. The loose crank b is prolonged back
that is formed with an arm b' on the opposite side of the shaft, and this arm forms
the nut for a screw h, which is fitted with a loose wedge piece n, which can be
pushed in between the aforesaid back prolongation 61 of the loose crank b, and a
back prolongation g' of the fixed crank g on the screw is fixed a friction wheel m,
which can be turned in one direction or the other by frictional contact with one of
two not revolving wheels or discs 1, 1, which slide together or separately in the
direction of the axis of the shafts, and are placed one on each side of the friction
wheel 'm on the screw h. When this latter has thus by frictional contact between
one of the discs or l¹ and the wheel m on the screw / been turned so far and in
that direction as that the wedge piece n touches the said prolongations b¹ and g¹
and presses them apart, then the brake is released, and vice versa, when the screw h
is turned in the opposite direction by means of the other stationary dise l' or 1, then
the screw is turned in the opposite direction, and thereby the brake coupling is
closed again. The two stationary discs l, l', may be hung or guided in prisms or
by parallel motion.
As I have thus described an example of coupling and uncoupling of two shafts,
so may the same object be carried out with regard to strap pulleys, V pulleys, or
wheels on their respective shafts, whether the pulleys or wheels are driving or
driven.
Figures 5 and 6 illustrate the Invention as applied to winches or cranes or other
hoisting or lowering gear. The coupling may be on a driving or an intermediate
shaft, or on the winding barrel shaft, but in each case it is made to connect and dis-
connect the shaft on which it is placed with a driving wheel thereon. If the
coupling is closed, which is caused by turning such a shaft in one direction, then 5
the load is being raised. By providing the loose crank b with a ratchet wheel o,
and placing therein a firmly supported pawl p, the load will be supported in place
even if the winch handle q is let go, because it itself tightens up the brake band if
a pressure be exerted on the winch handle q opposite to that required to raise the
load, or in other words, if the winch handle is turned back, then the loose crank 5
and the fixed crank will approach each other, and the load, more or less braked or
retarded, will descend. This form of brake or coupling has the peculiar advantage

page_text: that the driving shaft, with its winch handle or handles, does not revolve during
the descent of the load, thus preventing a great danger of accidents to the labourer,
also the advantage that the load is braked into a state of rest when the labourer
places the pawl in the ratchet wheel and leaves the winch handle. I thus attain
the same advantages as by the Megy-Stauffer winches, but in a different manner.
To illustrate the example of the application of the coupling to give a shaft
varying speed of rotation no Drawing is needed. Supposing a shaft has several
driving pulleys with different speeds of rotation, and each has such a coupling, then
a disconnecting appliance is only needed for the transmission of the greater speed
to the shaft, for by the free motion of the two cranks b and g towards each other
the quicker moving driving pulley will carry the shaft with it, this latter loosening
the coupling of the slower moving driving pulley.
Instead of the brake band being directly connected to the block d, as shewn
and described, it may be indirectly connected, or instead of such brake band one or
more brake blocks or shoes acting against the circumference of a brake drum may
be directly or indirectly connected to or form part of the block d. Figure 7 illus-
trates such an arrangement where the block or piece d has jointed to it a brake
block d acting as a brake against the drum e.
By naming these examples I do not pretend to have exhausted the modes or cases
of applications of this coupling, but they are given as illustrations only.
I claim, Firstly. The application of the above described brake apparatus for the
purpose of establishing a firm or disconnectable coupling of two rotating pieces of
machinery, be it shafts, or wheels, or driving pulleys, or combinations of such parts,
of which one is the driving part, and both being in the same axis of rotation, all
substantially as and for the purposes set forth.
Secondly. The combination with the driving and driven shafts of the crank g
attached permanently to the driving shaft, the drum e attached to the shaft to be
driven, the arm b' that is loose upon the shaft, the swinging block & pivotted to the
arm b, and having a slotted arm that is connected to the crank g, and the brake
block or band acted upon by the swinging block a, substantially as set forth.
In witness whereof, I, the said Eduard Becker, have hereunto set my hand
and seal, this Twenty sixth day of May, One thousand eight hundred
and seventy nine.
EDUARD BECKER (L.S.)