Year: 1894

page_text: A communication by THE CHALLENGE HIGH SPEED ENGINE COMPANY, of
Louisville, in the County of Jefferson and State of Kentucky, United States
of America.
I, WILLIAM Phillips Thompson, F.C.S. M.I.M.E. of The Agency for
Foreign Patent Solicitors, 6 Lord Street, Liverpool, and 6 Bank Street,
Manchester, both in the County of Lancaster, and 323 High Holborn in the
County of Middlesex, Civil Engineer, 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 :-
This invention is an automatic cut-off, direct acting, rotary engine.
The piston is formed with an odd number of longitudinal alternating lobes and
a similar number of intermediate depressions, the depressions gradually merging
into the lobes, and vice versa. Its diameters, however, taken through its axis from
any point are equal. On the cylinder are mounted one abutment valve for each
lobe and each depression on the piston, arranged at equal distances apart;
diametrically opposite abutment valves being connected together, and one of such
connected valves will be opposite a depression in the piston when the other is
opposite a lobe, and they are kept in close contact with the surface of the piston,
which acts as a cam, and when one valve is forced outward by a lobe of the piston,
the opposite connected valve is drawn into a depression in the piston diametrically
opposite such lobe.
The piston is axially centered in the cylinder, the outermost portions of the lobes
fitting closely against the inner wall of the cylinder, so that longitudinal chambers
are formed in the cylinder between the lobes of the piston. These chambers are
longitudinally divided by the non-rotatable abutment valves, but are not fixed
because the chambers move with the piston.
Steam is admitted at one side of each abutment valve occupying a depression
of the piston, and simultaneously exhausted_at the opposite sides of such valves ;
the steam, expanding between the cylinder, abutment valves, and lobes of the
piston, will rotate the piston sufficiently to move the lobes past the abutment
valves which were on top thereof when the engine started, and then the steam is
admitted between. such valves and the lobes. As soon as the steam pressure
between and against any two adjoining abutment valves is equalized, the inlet
valve is closed, and the outlet valve opened. In an engine having a three-lobed
piston, and six abutment valves, as shown, steam is first admitted at three
equidistant points simultaneously, and exhausted at three intermediate equidistant
points; and then steam is exhausted at the first three points, and admitted at the
latter three points, during each complete revolution of the piston.
When
The pressure of the steam in the chambers upon the piston is counterbalanced,
and consequently there is no lateral thrust of the piston on main shaft.
steam is admitted behind one valve, it is exhausted in front of the connected
diametrically opposite valve. As the piston rotates, the latter valve is moved
inward at the same speed and to the same extent that the former valve is moved
outward, until a lobe has moved past the inlet port beside the latter valve, when
steam is admitted thereagainst; thus the amount of abutment valve surface and
effective piston surface against which the live steam is working is substantially
maintained at all times; the amount of abutment surface presented by one of

page_text: each pair of diametrically opposite valves being increased in the exact ratio that
the amount of abutment surface presented by the other of such valves is diminished,
and vice versa.
The induction valve mechanism consists of three disks; the outer and inner
disks are non-rotatable and have equidistant slots corresponding in number to the
abutment valves of the engine, and the slots of the inner disk communicate with
ports leading through the cylinder walls beside the respective abutment valves.
The intermediate disk has half as many equidistant perforations in it as the other
disks have slots, is fixed on the main shaft, and rotates with the piston. The
disks are all enclosed in a steam chest on the end of the cylinder. The slots in
the outer and inner disks coincide, and only when the openings in the intermediate
disk coincide with the slots in the other disks can steam enter the cylinder. As
there are only half as many perforations in the intermediate disk as there are
slots in the other disks, steam will be simultaneously admitted into the cylinder
only through every other port, but all the ports will be opened once during each
revolution of the piston.
A similar valve mechanism can be used for the exhaust ports.
To regulate the admission of steam, the inner disk may be partially turned and
thus vary the extent of registration of its slots with those of the outer one. The
intermediate disk admits steam only through such parts of the slots of the inner
disk as happen to coincide with the slots in the outer disk, so that turning the
inner disk serves to lengthen or shorten the steam ports; therefore steam enters
when and while the perforations in the intermediate disk are passing between such
parts of the slots of the inner and outer disks as coincide with each other.
governor can be used to control the position of the inner disk, and thus automatically
regulate the steam supply and the speed of the engine.
A
The accompanying drawings illustrate one form of engine and the valve
mechanism embodying this invention; and, referring thereto by figures and letters
of reference :
Figure 1 represents a perspective view of the engine.
Figure 2 is a longitudinal vertical section through the same.
Figure 2 is a detail longitudinal section showing the valve ports.
Figure 3 is a face view of the valve mechanism partly in section.
Figure 4 is an end view of the cylinder with head removed showing interior
parts.
Figure 5 is a perspective view of an abutment valve.
Figure 6 is a detail view of one of the cylinder heads.
Figures 7 and 8 are detached views of valve disks.
The cylinder A is mounted on a suitable base. Each cylinder head B has an
annular chamber, b, in its exterior face (in which are fitted the valve disks), and a
central opening for the passage of main shaft C. The chambers, b, are closed by
removable plates D provided with stuffing boxes d, in which shaft C is journaled.
The piston E has three lobes e, and three intermediate depressions e'. Six equi-
distant abutment valves F. F, arranged radially around the piston, are protected.
by housings F1 attached to the cylinder and play through slots therein as shown.
Diametrically opposite valves F, F, are rigidly connected by bars f (lying in
radial grooves in the inner faces of heads B) slotted at for the passage of
shaft C, and to permit their longitudinal movement in the grooves. These bars
cause the connected valves to move simultaneously, and the surface of the piston
serves as a cam to actuate the valves. At one side of each abutment valve is a
longitudinal inlet port G closed at one end and communicating at the other end
with one of the ports g in one head B. And at the opposite side of each abutment
valve is a similar exit port H closed at the end adjoining port g, but communi-
cating at the other end with one of the exit ports h in the other head B.
The inlet valve consists of three disks J, K, L; disk J is non-rotatable, but is
centered on the end of shaft C within chamber 6, and has six equidistant slots j,
adapted to register with ports 9. Disk K is similar in size to disk J, but its hub k

page_text: is splined on shaft C, it also has but three openings ¹. Disk L is similar to
disk J, having six slots 1, and mounted on the hub of disk K, but is kept from
rotating by a set screw L'. Disk K rotates with the piston, and, as it rotates,
openings register with three alternate slots j, and l, alternately, and steam is
then admitted into the cylinder and the engine is operated as above described.
The exhaust valve is like the inlet valve, but the intermediate disk K thereof
is secured on shaft C, with its openings relatively intermediate the openings in the
disk K of the inlet valve, consequently steam will be exhausted from one side of
the abutment valves simultaneously with its admission at the other side thereof;
as indicated in Figure 4.
S is the induction and s the eduction steam pipes. Disk J of the inlet valve
has a segmental rack J' on its periphery which is meshed by a pinion m on a
stub shaft M journaled in the head and plate, as indicated in the drawings, and
a small pinion m¹ is fixed on the outer end of said shaft, and meshed by a segmental
rack N, connected in any suitable manner with a governor n, which is driven
from the main shaft, therefore, when the speed reaches the maximum point, the
governor will rock shaft M, and thus cause a slight rotation of disk J, thereby
shortening the extent of registration of the perforations in disk K simultaneously
with slots in disks J and L, and consequently lessening the supply of steam to
the engine.
The engine can be reversed by admitting steam at the exhaust side and
exhausting it from the inlet side.
The piston may have a greater number of lobes than is shown, provided there
is an unequal number thereof, and that it continues of equal diameters at all
points. The engine must have an equal number of abutment valves in order that
the diametrically opposite valves may be connected and operated as above
described. In some cases, disk J of the valve mechanism may be fastened to the
head; or instead, as an equivalent construction, the face of the head can be
dressed so that the disk J can be omitted and disk K work directly against the
head, in the bottom of chamber b.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, as communicated to
me by my foreign correspondents, I declare that what I claim is :-
1. In a rotary engine, the combination of a piston of equal diameters throughout,
having an odd number of longitudinal lobes; with a series of equidistant abutment
valves arranged in pairs, one pair for each lobe of the piston, the members of each
pair being diametrically opposite, and rigidly united so as to move synchronously;
the said valves being operated only by the piston and their mutual connection,
substantially as described.
2. The combination of the cylinder and piston therein and abutment valves ;
with the inlet ports beside each valve, and valve mechanism substantially as
described for admitting steam successively into alternate ports and to three or more
of such ports at a time, substantially as described.
3. In a rotary engine, the combination of the cylinder, a piston having an odd
number of longitudinal lobes, and a similar number of intermediate depressions;
and a series of abutment valves one for each lobe and depression of the piston ;
with means for admitting steam at one side of three or more alternate valves at a
time, until all the valves have been in active work once during each revolution of
the piston, and means for exhausting steam at the other side of such valves,
substantially as described.
4. In a rotary engine, a concentric piston of equal diameters throughout, having
an odd number of longitudinal lobes, in combination with a series of equidistant
abutment valves arranged in pairs, one pair for each lobe of the piston, the
members of each pair being diametrically opposite and rigidly united and
mechanism for admitting steam against one valve of each pair and exhausting it in
front of the opposite valve, substantially as described.

page_text: 5. The herein described valve mechanism for rotary engines, consisting of three
disks, the outer and inner non-rotatable disks having corresponding slots, and the
intermediate rotatable disk a perforation adapted to intermittently register with
those of the outer and inner disks, substantially as described.
6. The combination of an engine cylinder, having an even number of inlet
ports, with a rotating disk having half as many openings adapted to simultaneously
register with alternate ports, substantially as specified.
7. The combination, in a rotary engine, of the cylinder having an even number
of equidistant ports; and a piston; with a rotating disk revolving with the piston
provided with equidistant openings adapted to simultaneously register with three
or more alternate cylinder. ports and to register with all the cylinder ports once
during each revolution thereof, substantially as set forth.
8. The combination of the cylinder, its equidistant inlet ports, the rotating
piston, the disk mounted on the piston shaft having equidistant openings adapted
to simultaneously register with three or more alternate cylinder ports, and
diametrically opposite abutment valves intermediate the cylinder ports, the opposite
valves being connected, substantially as described.
9. The combination of the cylinder, its inlet ports, and the piston and main
shaft; with the valve mechanism consisting of three disks, the inner and outermost
disks being stationary and having corresponding slots equal in number to the
ports of the cylinder, the slots of the inner disk communicating with said ports;
an intermediate rotating disk having openings adapted to register with alternate
openings in the outer disks, and mechanism whereby the inner disk may be
slightly rotated so as to vary the length of register between the openings in the
intermediate disk and the slots in the outer and inner disks, substantially as
.described.
.
Dated this 12th day of March A.D. 1894.