Improvements in Reversible Rotary Steam Engines.
Year: 1897

page_text: COMPLETE SPECIFICATION.
Improvements in Reversible Rotary Steam Engines.
I, GEORGE ESTER WOODARD, of Sugar Groove, in the County of Warren, and State
of Pennsylvania, United States of America, Clerk, 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 :—
My invention has relation to improvements in reversible rotary steam engines,
and the object is to simplify the construction and increase the efficiency of the
same. To this end the novelty consists in the construction, combination and
arrangement of the same as will be hereinafter fully described and particularly
pointed out in the claim.
In the accompanying drawing the same reference characters indicate the same
parts of the invention.
Figure 1 is a perspective view of my improved reversible rotary steam engine;
Figure 2 is a vertical section of the same;
Figure 3 is a transverse section;
Figure 4 is a side elevation, with the steam-chest cover removed;
Figure 5 is a similar view, with the steam-chest and reversing valve removed;
Figure 6 is a detail view of the valve, and
Figure 7 is a detail view of the plunger.
1 represents the horizontal base plate, cast integral with the vertical frame 2,
which is formed with a circular transverse orifice 3, constituting the cylinder of the
engine; and 4-4 represent the cylinder heads, removably secured by bolts 5-5 to
the opposite parallel sides of the frame 2.
6 represents the rotary disk piston fixed on the shaft 7, journaled in the integral
bearings 8-8 in the cylinder-heads 4-4. The diameter of this disk-piston is
smaller than the diameter of the cylinder in which it rotates, and its periphery is
divided by equidistant radial transverse rectangular recesses 9-9, formed with
smaller aligned radial recesses 10-10.
12-12 represent rectangular plungers arranged in the recesses 9, their outer
curved ends corresponding to and abutting against the inner face of the cylinder,
while their inner ends rest upon the coiled springs 13 located in the aligned
recesses 10, and which serve to force the plungers outwardly and insure a steam-
tight joint between the outer end of the plungers and the face of the cylinder.
14 represents the steam inlet passage, and 15 a vertical transverse recess formed
in the rectangular portion 16 of the frame, which receives a vertical sliding block 17,
the lower end of which rests upon the periphery of the piston, being held in
intimate contact therewith by means of the spiral springs 18, 18 resting upon the
top of said block, and held in contact therewith by means of the cap 19 secured in
the upper end of the recess 15.
20 represents an oil passage in said cap, communicating with an oil cup 21 fixed
in the upper end of said cap, and through this means the piston is lubricated.
22 represents the exhaust passage communicating with a cylindrical chamber 23,
and two ports 24 and 25 lead from the inlet passage 14 and extend on opposite sides
of the block 17 and communicate with the cylinder 3.
26 represents a semicircular valve mounted on a transverse valve stem 27, and
adapted to alternately cover the ports 24 and 25. It is also adapted to partially

page_text: or wholly close one port and act as a throttle valve, while the opposite port remains
entirely closed.
29 represents the throttle lever fixed on one end of the valve-stem 27, and its
upper end is provided with the usual pivoted grip-pawl 28, which engages the
segmental rack fixed to the side of the steam-chest.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is
A rotary steam engine, comprising the horizontal base 1 and integral frame 2
provided with the transverse cylindrical orifice 3, the inlet passage 14, the vertical
recess 15, the inlet ports 24 and 25, and the exhaust port 22 in combination with the
rotary disk piston 6, having the radial recesses 9 and the aligned recesses 10,
the spring 13 arranged in said recesses 10, the plungers 12 fitted to the recesses
9, the block 17 mounted in the vertical recess 15, the springs 18 and the cap 19
provided with the oil passage 20 and the oil cup fixed to said cap, the steam-chiest
formed with the cylindrical chamber 23 and the semicircular valve 26 mounted in
said chamber and arranged to alternately or simultaneously close said ports 24
and 25, substantially as shown and described.
Dated this 7th day of Decembar 1807