IMPROVEMENTS IN DONKEY ENGINES AND PUMPS
Year: 1876

page_text: LETTERS PATENT to Joseph Stannah, of Southwark, in the County of Surrey,
Engineer, for the Invention of "IMPROVEMENTS IN DONKEY ENGINES AND
PUMPS."
Sealed the 21st October 1870, and dated the 24th April 1870.
PROVISIONAL SPECIFICATION left by the said Joseph Stannah at the
Office of the Commissioners of Patents on the 24th April 1876.
JOSEPH STANNAH, of Southwark, in the County of Surrey, Engineer.
PROVEMENTS IN DONKEY ENGINES AND PUMPS."
" IM-
This Invention relates to improvements in actuating the valves of that class of
engines known as " donkey engines or pumps for supplying steam boilers, in
which the piston rod of the cylinder and the plunger of the pump are made in
one piece.
From a pin or projection on the frame or bed of the engine an arm or pendulum
swings, having a small disc or plate of metal free to move on a pin or projection on
the other end of the arm or pendulum. This disc near the edge is firmly attached
to a metal pin passing freely through the cross head of the engine, and fixed
into a similar disc on the other side of the cross head to which the valve spindle is
attached.
By reason of this arrangement fly wheels, guide bars, connecting rods, and
eccentrics are not required.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Joseph Stannah in the Great Seal Patent Office on the 23rd October
1876.
JOSEPH STANNAH, of Southwark, in the County of Surrey, Engineer.
PROVEMENTS IN DONKEY ENGINES AND PUMPS."
"IM-
This Invention relates to improvements in actuating the valves of that class of
steam engines known as donkey engines or pumps for supplying steam boilers
15
"

page_text: Figure 2 shows a vertical section, and Figure 1 part of a front view of a donkey
engine arranged and constructed in accordance with my Invention.
From a pin a fixed on the frame bed, or other convenient part of the engine, an
arm or pendulum b swings having a small disc or plate of metal e free to move on
a pin or projection on the other end of the arm or pendulum b. This disc c near
the edge is firmly attached eccentrically to a metal pine passing freely through
the cross head f of the engine, and connected to a similar disc g on the other
side of the cross head f to which the valve spindle is attached, so as to actuate
the valve.
Figures 3, 4, and 5 show several views of a modified arrangement of donkey
engine constructed in accordance with my improvements, in which the pin a¹ of
the pendulum b¹ may be made to act directly upon one or more valves, cocks, or
steam ports. In this arrangement the pin e¹ of the cross head f¹ is connected to
the disc c¹ in a similar manner to the arrangement previously described. The semi-
rotating steam valve is actuated by the square end o¹ of the pin a¹ upon which the
pendulum is fixed.
By reason of this pendulum arrangement the ordinary fly wheels, guide bars,
connecting rods, and other parts are dispensed with, the action of the parts being
regulated by the movement of the pendulum, thereby simplifying and reducing the
cost of the pump, and also the number of working parts, thus making it a very
available donkey pump, and also a useful steam pump applicable to fire-engines and
other purposes.
Having thus described the nature of my Invention, and the manner of carrying
the same into practice, I would have it understood that. I do not limit my claim to
the exact details herein described, as the same may be varied without departing
from the true character of my Invention; but what I claim is, the improved arrange-
ment and construction of donkey engines and pumps, in which a pendulum bis
employed to actuate the steam valves, substantially in the manner and for the
purposes herein-before described and represented in the Drawings hereto
annexed.
In witness whereof, I, the said Joseph Stannah, have hereunto set my hand
and seal, this Twenty-first day of October, in the year of our Lord One
thousand eight hundred and seventy-six.
J. STANNAH. (L.S.)