Improvements in Shaft Couplings.
Year: 1892

page_text: Date of Application, 13th Aug., 1892-Accepted. 17th Sept., 1892
Improvements in Shaft Couplings.
I, VICTOR HARRY CRUSE, of Front Street, Seaton Carew, in the County of
Durham, 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 construction of shaft couplings of the usual boss
and flange type, the flanges of which are secured together to effect the required
connection.
It is found in practice that shafts which are coupled together for the transmission
of rotary motion although nominally of the same diameter vary sufficiently to
cause considerable difficulty in coupling them together without resorting to couplings
specially adjusted to suit each case, it being essential to get good surface contact
between each coupling and the shaft on which it is fixed.
The essential feature of my invention consists in substituting for the flange bolts
hitherto used two or more flange connecting strips or duels in which are combined
the requisite strength and rigidity to transmit the torsional strain from shaft to
shaft is combined with a sufficient flexibility to adjust the said connecting strips or
duels to such deviation from the dead true position in the coupling flanges
as is due to the possible variation in the diameters of the shafts to be coupled
together.
And in order that my invention may be clearly understood and readily carried
into effect, I will now refer to the accompanying drawing in which
Figure 1 illustrates in part section my improved couplings connected together
in the working position on the shafts, corresponding to which Figures 2 and 3 are
a part sectional end view and plan respectively.
In the figures, the sections A'B' are duelled together by the connecting strip C¹,
and the corresponding sections A' B' are similarly duelled together by the strip C³;
the two corresponding sections of the couplings on each shaft being bolted tight onto
the shaft by bolts passing through the wings or flanges D, in addition to which the
couplings are keyed on the shaft if required as shown in Figure 1. These connecting
strips or duels are preferably steel plates of considerable width relatively to their
thickness and are secured end wise in the flanges of the couplings and flatwise to
the plane of division between the sections of the couplings in the manner shown,
that is to say that they are placed in the moulds in which the couplings are cast,
the enveloping metal of which grips them firmly in the well known manner when
set.
The couplings are split as shown, the line of division E between the sections
taking the direction of a diameter between the flanges D. It must be understood
that two connecting strips C¹C placed at opposite parts of the coupling flanges
with the plane of division E coming half way or thereabouts between them will
generally serve the purposes of my invention and when fixed in the position as
clearly shown in Figures 1 and 2 it will be observed that whilst they are designed
to be rigid in the direction in which they receive the torsional strain transmitted
between the couplings they are sufficiently thin to bend laterally to the extent
required for separately adjusting each coupling to its position on its shaft when a
difference of diameters in the shafts or equivalent inequalities have to be provided
for. But when the torsional strain to be transmitted is exceptionally heavy I
prefer to distribute the requisite sectional area over more than the two connecting
strips or duels shown in Figures 1 and 2 by placing them as for instance two and
two together in the manner shown in Figure 4, by which sufficient sectional area
may be obtained without sacrificing the requisite flexibility of the said connecting
strips to bend laterally as hereinbefore explained with reference to Figures 1 and 2,

page_text: or in other equivalent positions providing that these connecting strips are set as
nearly flatwise as possible to each other and to the line of division E between the
sections of the couplings, otherwise their mutual effect upon each other would con-
stitute a rigid connection between the couplings which would defeat the purpose of
my invention.
Although the mode in which the couplings are cast forms no part of my inven-
tion providing the distance pieces C₁ Care secured to opposite coupling flanges in
the manner required, I wish to explain that two opposite sections as A'B' can be
cast in one, and the other two opposite sections AB be also cast in one, or if
preferred, all four parts can be cast together, proper parting pieces being provided
to form the joint at E.
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 the construction of shaft couplings of the ordinary boss and flange type, the
use of the flexible distance pieces or duels CC in substitution for bolts, by which
the opposite flanges are secured together in such a manner that whilst the said
distance pieces or duels rigidly transmit the torsional strains from one shaft to the
other, they are flexible in the required direction for separately adjusting each
coupling to its shaft, substantially as and for the purpose as hereinbefore described
with reference to the accompanying drawing.
Dated this 12th day of August 1892
G. J. CLARKSON,
Stockton-on-Tees, Agent for the Applicant.