Improvements in Friction Couplings.
Year: 1899

page_text: Date of Application, 14th Nov., 1899-Accepted, 20th Jan., 1900
Improvements in Friction Couplings.
I, EBERHARD SEGER, of 40, Kammakaregatan, Stockholm, in the Kingdom of
Sweden, Mechanical 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 friction couplings of the kind in which the coupling-
action is brought about by the aid of a coiled spring mounted on one half of the
coupling, which spring in the position of engagement is enveloped by a spring-
box secured to the other half of the coupling, and against the inside of which box
the spring is forced when expanded
The object of my invention is to so arrange such couplings, that they will act
whether the driving-shaft revolves in one direction or in the other; this has not
been the case with the couplings of this kind heretofore used, such coupling having
been capable of operating in one direction of motion only of the driving shaft.
In the accompanying drawings I have shown a friction coupling constructed in
accordance with the present invention,
Figure 1 is an elevation, the belt-pulley being in section;
Figure 2 is an elevation of the coupling-sleeve with its spring inserted;
Figure 3 is a longitudinal section of the coupling, and
Figure 4 an elevation of the coupling-sleeve without its spring.
a is the shaft, and b the belt-pulley loosely mounted on it, and having its hub
secured to a spring-box c which can revolve on the shaft a, but is prevented from
moving axially by means of collars c. d is a sleeve which is adapted to slide,
but not rotate, on the shaft, and which can be pushed more or less into the spring-
box c.
Around the circumference of this sleeve is wound a spiral spring e, the
two ends of which bear against shoulders g, h, on the end-flanges of the sleeve d
(Figures 2, 4) which flanges, moreover, on their inside, are shaped so as to fit the
end-coil of the spring bearing against them. The sleeve is provided with a
groove k, in which engages a suitable coupling-bar or like device for introducing
the sleeve into, or extracting it from, the spring-box for the purpose of effecting
an engagement or disengagement of the coupling.
When the sleeve d, rotating with the shaft a, is introduced into the spring box
while the latter is at a standstill, the spring e is forced against the inside of the
box, and a considerable amount of friction will be generated between the parts,
and as a consequence, the spring, striving to expand, will obtain an increasing
hold of the box. The force transmitted from the shaft will act on the ends of
the spring at either of the shoulders g, h (depending on the direction of rotation
of the shaft), and as a result the molecules of the spring will, during the trans-
mission of power, be subjected to compression. By thus constructing the coupling
in such a manner, that each end of the spring will, according to the direction of
motion, be acted on by a power-transmitting bearing or shoulder acting through
the middle line of the section of the spring at its point of abutment against the
shoulder, it is possible, when the coupling-halves are brought together, to produce

page_text: the aforesaid expansion of the spring no matter in which direction the driving-
shaft a revolves, because one of the bearings or shoulders g, h will obviously,
always act on the spring-end in its path, and thus it is possible to make the
coupling to act in either direction of motion of the driving-shaft a. In friction-
'couplings of the kind heretofore used, no such bearings or shoulders at both
ends of the spring have been employed.
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
I claim is:-
In friction-couplings in which the coupling-action is produced by the aid of a
coiled spring mounted on one half of the coupling, which spring in the coupling-
position, is enveloped by a spring-box secured to the other half of the coupling,
the combination of the said spring and two bearings or shoulders one at each end
of the spring and so connected with each other and with the half of the coupling
first mentioned that the bearing or shoulder will, in operation, act upon the spring,
expanding the latter, when power is transmitted so as to force the spring against
the spring-box, thus effecting a coupling action no matter in which direction the
coupling-half first mentioned revolves, substantially as herein described and illus-
trated by the accompanying drawings.
Deted thin 14th law of N
1000
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.