Steam Air,
Year: 1887

page_text: ALEXANDER GILCHRIST Junr. Brassfounder 25 Eglinton Street Glasgow JOHN
HANNAN, Engineer 103 Dundas Street South Side, Glasgow do hereby declare the
nature of this invention to be as follows:-
This invention is an appliance for moving the Slide or piston Valves of Steam, Air,
Water or other motive power engines, and is accomplished as follows.
By placing a flat bar with parallel edges parallel to the piston rod the ends of this
bar are tapered so as to form an equilateral triangle one side of which runs across
the bar, this bar is attached to the valve spindle and is made to slip backward and
forward, a distance equal to the travel of the valve, the perpendicular of the angle
from the side running across the bar being equal to the travel of the valve.
This bar is made to slip backward and forward by two pullies, and a spring which
is attached to and carried with the piston rod. The spring is arranged to force the
pullies against each side of the bar with a force towards the centre of the bar, so that when
the pullies come to the angles they force the bar backward, and shift the valve to give
steam, air, water or other motive power to the piston which when it travells to the other
end of the stroke comes on to the angle and shifts the valve for next stroke forward.
Or it may be done by having two parallel flat bars one on each side of the piston
rod, and the pullies between them and the spring for causing the pullies to force
against the edge next to the piston rod, by having these bars fixed to the valve
spindle and angles cut in the ends so that the pullies may shift them.

page_text: COMPLETE SPECIFICATION.
An Improved Valve Gear for Steam and other Fluid Pressure
Engines.
ALEXR. GILCHRIST Junr. Brassfounder 25 Eglinton Street Glasgow JOHN HANNAN
Mechanic 103 Dundas Street S. S. Glasgow 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:-
--
The drawings are the same as those left with the Provisional Specification.
This invention is an appliance for moving the slide or piston valves of Steam, Air,
Water, or other motive power Engines and is accomplished as follows-
By placing a flat bar with parallel edges parallel to the piston rod, the ends of this
bar are tapered so as to form an equilitarel triangle, one side of which runs across
the bar.
This bar is attached to the valve spindle and is made to slip backward & forward a
distance equal to the travel of the valve, the perpendicular of the angle from the side
running across the bar being equal to the travel of the valve. This bar is made to
slip backward & forward by two pullies and a spring, which is attached to and carried
with the piston rod. The spring is arranged to force the pullies against each side of
the bar, with a force towards the centre of the bar, so that when the pullies come to
the angles they force the bar backward and shift the valve, to give Steam, Air, Water,
or other motive power to the piston which when it travels to the other end of the
stroke comes on to the angle and shifts the valve for next stroke forward.
Or it may be done by having two parallel flat bars one on each side of the piston
rod, and the pullies between them, and the spring for causing the pullies to force
against the edges next to the piston rod, by having these bars fixed to the valve
spindle and angles cut in the ends so that the pullies may shift them.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed 1 declare that what [
claim is.
An improved method for shifting valves of steam and other fluid pressure Engines
as heretofore described.