IMPROVEMENTS IN STEAM AND OTHER SUCH LIKE MOTIVE-POWER ENGINES
Year: 1876

page_text: PROVISIONAL SPECIFICATION left by Alexander Guthrie at the Office of
the Commissioners of Patents on the 4th March 1876.
ALEXANDER GUTHRIE, of Number 45, Gainsford Street, Horselydown, in the
County of Surrey. "IMPROVEMENTS IN STEAM AND OTHER SUCH LIKE MOTIVE-POWER
ENGINES."
My Invention relates to improved means of transmitting motion from the
reciprocating pistons of steam or other such like motive-power engines to the crank
shafts, whereby increased facilities are obtained for reversing the direction of
motion of such engines, and a single cylinder and reciprocating piston may be made
to give motion to several shafts, turning them all in one direction, if desired, or
some of them in one direction, and the others in the reverse direction without the
use of fly wheels, driving straps, springs, or toothed gearing.
The arrangements are especially applicable to marine engines, in which it is
sometimes necessary or desirable to turn one paddle wheel or screw propeller in one
direction, and the other paddle wheel or screw propeller in the opposite direction.
According to existing arrangements of marine engines it is usual to employ a
separate cylinder and piston, or separate pairs of cylinders and pistons for each
paddle wheel or screw propeller. According to my Invention these effects can be
obtained by means of one cylinder and piston only.
The Invention consists of a peculiarly constructed crank having a crank pin
working loosely in connection therewith, but so arranged that when actuated by
the piston of the engine, the said loose crank pin is caused to effect each semi-
revolution of the crank, partly by direct action on the crank, and partly through
the intervention of a second or supplementary adjustable crank pin connected to the
aforesaid loose crank pin by means of plates or connecting links, by which
arrangement the engine, although single cylindered, has no dead centres, and can
be started at any position of the piston in the cylinder. Plates or links connect
the supplementary adjustable crank pin with the crank itself in such manner that
the position of the former, with regard to the crank and loose crank pin, can be
adjusted so as to cause the crank shaft to revolve in either direction at pleasure.
Guide or safety tappets are connected with the aforesaid plates or links, or some
of them, for the purpose of preventing recoil of the crank shaft, and to ensuro
proper action on the crank of the aforesaid loose crank pin when the piston is at or
near the top and bottom of its stroke. They operate in connection with corre-

page_text: sponding restraining abutments or guide surfaces carried on or operated by means
of a cross head connected to the piston rod of the engine; or, if preferred, abutments
or guide surfaces may be fixed on the frame or other suitable part of the engine for
the purpose of guiding the loose crank pin in its path at or near the top and bottom
of its revolution. The said cross head may be the means of communicating motion
from the piston rod of the engine direct to the aforesaid loose crank pin or pins of
the crank or cranks through the medium of a slot or slots of suitable shape formed
in the said cross head; or if preferred, the ordinary connecting rod or rods may be
employed for communicating motion from the piston rod cross head to the said loose
crank pin or pins.