Improvements in Coupling Rods for Transmitting Rotary Motion to One or More Shafts, suitable for Cycles, Motor Carriages, and Ships.
Year: 1896

page_text: Date of Application, 15th Dec., 1896
Complete Specification Left, 14th Sept., 1897-Accepted, 20th Oct., 1897
PROVISIONAL SPECIFICATION.
Improvements in Coupling Rods for Transmitting Rotary Motion to
One or More Shafts, suitable for Cycles, Motor Carriages, and
Ships.
JOHN WARDEN BAIRD Pilmore House, Pencaitland East Lothian N.B. Engineer,
I do hereby declare the nature of this invention to be as follows:-
The object of this invention is to dispense with chain driving in cycles and
motor carriages. This coupling rod can also be used to transmit power in ships
fitted with two or more propellers, one set of engines only being necessary.
This invention is performed as follows. The coupling rod is fitted to three or
more cranks or eccentrics, preferably the rod is coupled to three cranks. The
centres of two of these cranks are in line with each other; the third crank with
its shaft is placed mid way or otherwise suitably placed between the other two
cranks but not in line with them, being placed to one side. The bearings of the
shafts to which the rod is coupled by means of the cranks or eccentrics run in
suitable journals either ball or plain. The form of the coupling rod is triangular
with a crank or eccentric coupled by means of suitable bearings to each corner
of the triangle. With this arrangement of a three cranked coupling rod there
are no dead centres. When power is applied to any one of the three cranks the
other two follow in the same direction. Supposing two of the cranks are on their
dead centres, the third crank is not then on its dead centre but is free to lift the
rod laterally and simultaneously the other two cranks are taken over their dead
centres.
Dated this 14th day of December 1896.
Improvements in Coupling Rods for Transmitting Rotary Motion to
One or More Shafts, suitable for Cycles, Motor Carriages, and
Ships.
I, JOHN WARDEN BAIRD, formerly at Pilmore, Pencaitland, East Lothian, but
now at 8 Mentone Avenue, Portobello, do hereby declare the nature of my
Invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement, that is to say:-
The object of this invention is to dispense with chain driving in cycles and
motor carriages. This coupling rod can also be used to transmit power in ships
fitted with two or more propellors, one set of engines only being necessary.
[Price 1

page_text: This invention is performed as follows:-
The coupling rod is fitted to three or more cranks or eccentrics, preferably the
rod is coupled to three cranks. The centres of two of these cranks are in line
with each other the third crank with its shaft is placed mid way or otherwise
suitably placed between the other two cranks but not in line with them being
placed to one side. The bearings of the shafts to which the rod is coupled by
means of the cranks or eccentrics run in suitable journals either ball or plain.
The form of the coupling rod is triangular with a crank or eccentric coupled by
means of suitable bearings to each corner of the triangle.
With this arrange
ment of three cranked coupling rod there are no dead centres. When any one
of the three shafts to which the cranks or eccentrics are attached is made to
revolve the other two shafts simultaneously rotate in the same direction.
Supposing two of the cranks are on their dead centres, the third crank is not
then on its dead centre but is free to lift the rod laterally and simultaneously the
other two cranks are taken over their dead centres.
Figure 1 is a side elevation, Figure 2 a plan view and Figure 3 an end view
broken away, showing the coupling rod d fitted to a safety bicycle to transmit the
driving power instead of a chain. It also can be used to transmit mechanical
power to cycles, a a¹ is a double barreled crank bracket. The pedal crank axle a³
is carried in the bracket a. As one end of this axle a² is keyed an internally
toothed wheel b. The other bracket a¹ carries a shaft c¹ at one end of which is
keyed the externally toothed pinion c. This pinion gears with the internally
toothed wheel b. At the other end of this shaft c' is a crank or eccentric A. By
means of suitable bearings this crank or eccentric A is coupled to the triangular
coupling rod d d d. The middle or controlling crank B is coupled to the triangular
coupling rod d with either a crank or eccentric. As shown in Figures 1, 2, and 3
the triangular coupling rod is coupled to the driving wheelf by means of an
eccentric C but the driving wheel may be connected to the coupling rod by means
of a crank and when so connected the bearings of the driving wheel will require
to be attached to the framing of the cycle. To diminish friction the eccentric C
shown in the drawings at the right side of driving wheel f is fitted with ball
bearings placed in a groove partly formed in the eccentric pulley and the eccentric
straps. I use the externally toothed wheel and externally toothed pinion for
speeding up the cycle but other gearing may be used, such as three spur pinions
or the sun and planet gearing.
This
Figure 4 shows the cross section of a steam ship with double cylinder engine
placed athwart ship coupled to the upper crank B of the three cranked coupling
rod ddd. The two bearings of the lower coupling rod d are connected by means
of cranks or eccentrics at A and C to two or more propellor shafts D.
triangular coupling rod d d d may be used to transmit power in steamers fitted
with ordinary screw propellors. Should however a steamer be required for parti-
cularly fast manoeuvring purposes then the coupling rod d is coupled to reversible
twin propellors. The engine or motor would then always run in the same
direction the reversing or manoeuvring being done by shifting the position of the
propellor blades. If reversible propellors were used in this system the vessel could
be reversed without even stopping the engines thus considerably saving time in
comparison with a steamer fitted with independent engines for each propellor which
if one or both engines had to be reversed they must necessarily be stopped and
started again before reversal could be accomplished. When the coupling rod is
used to transmit power in motor carriages it takes the place of the usual pitch
chain and is connected to the driving wheel or wheels by means of suitable gearing
in connection with the motor so that different speeds of running may be obtained.
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:-
The arrangement and use of a coupling rod connected to cranks or eccentrics

page_text: for transmitting motion to the shafts of cycles, motor cars, and ships, substantially
as herein described in reference to and shown in the accompanying drawings.
Dated the 13th day of September 1897.
W. R. M. THOMSON & Co.,
96 Buchanan Street, Glasgow, Agents.