IMPROVEMENTS IN THE VALVE GEAR AND IN THE METHOD OF REGU- LATING CORLIS' AND OTHER ENGINES
Year: 1876

page_text: PROVISIONAL SPECIFICATION left by François Joseph Lemoucho at the Office
of the Commissioners of Patents on the 18th May 1876.
FRANÇOIS JOSEPH LEMOUCHE, of St. Gilles les Bruxelles, in the Kingdom of
Belgium. "IMPROVEMENTS IN THE VALVE GEAR AND IN THE METHOD OF REGU-
LATING CORLIS' AND OTHER ENGINES."
This Invention relates to an improved valve gear for steam engines, completely
modifying the action of engines of the "Corlis" type, applicable also to all steam
engines whether land or marine of whatever power and speed.
By my very simplified arrangement and method of regulating by governor I
obtain a saving of about fifty per cent. in fuel and the very important advantage of
avoiding wear, there is therefore no fear of the engine getting out of order whilo
working.
This movement consists (see Figure 1 of the accompanying two Sheets of
Drawings)
Firstly. Of two toothed racks at top and bottom gearing with four toothed
quadrants, two of which are for admission of steam and two for exhaust; theso
two racks are guided by two cross pieces each carrying a socket or bush guiding
the central rod; these three pieces are united by two cross pieces, one at the top
the other at the bottom. The central rod is intended to be driven by the eccentric.
Secondly. Of four quadrants, two of which being for admission of steain, and
each carrying a steel tappet intended to open the valves for the entrance of steam
into the cylinder at the proper time. These two quadrants are set in two half
coupling boxes which are keyed upon the steel axle working the valves, they are
moveable on the axle working the valve as well as within the two couplings,
cach of which carries a small piece of steel dovetailed into it and fixed by two
screws.
Thirdly. The governor action consists of a rod carrying two oblique plates,
which rod is guided at top and bottom and is intended to receive the motion of the
governor. These two oblique plates work in two slides, each having a mortise
similar to that of the two oblique plates, the two slides are guided by two small
supports.
The action above set forth may be modified (as at Figure 4 of the Drawing) by
doing away with the toothed gearing and substituting two forked levers, each
provided with a sliding block working in suitable guides; two forked levers carry
thair tannets.

page_text: On the accompanying two Sheets of Drawing, Figure 1 (Sheet 1) is an elevation
showing the entire arrangements. Figure 2 is a plan of the same. Figure 3 is a
side elevation of a modification of the above arrangement, the forked levers being
substituted for the toothed gearing. Figure 4 represents the valve gear detached.
Sheet 2 represents the various parts detached and drawn to an enlarged scale.
a, a¹, racks working the two quadrants c, c¹, for admission of steam. b, b¹, racks
working the two quadrants d, d', for escape of steam or exhaust. e, f, couplings
with right and left handed screws for lengthening or shortening the racks.
g, h, cross pieces carrying the guides for rod . i, j, guides of the central rod k.
k, central rod screw threaded at top and bottom and intended to raiso or lower the.
valve gear. l, m, cross piece joining the racks and the rod. n, eccentric rod
c, c¹, quadrants carrying tappets o, o¹, intended to open the valves for admission of
steam into the cylinder. Directly the engine works the arms o, o¹, come against
the ends of the slide blocks p, p, to which a reciprocating movement is given by
the regulator; at the moment that the arms o, o, come against the points p, p,
the arms 9, 9, unclinch and permit the couplings to bring back the valve & (Sheet 2)
to its place by the power of the spring of the air pump; when the valve is in
position the piston of the air pump comes down to the bottom of its barrel.
u, lever keyed on the axles v, v³, of the valves. q', arm which takes into the steel
piece v. Directly 9 leaves the steel piece the quadrant c may make its entire
journey; when it comes back if the valve is not returned to its place, * comes
against y and forces the valve to resume its position as the springs, s, compel o
to put back into its place. a, a, axle of valves. b, b, place for boss of quadrant.
c, c, screw securing the steel keys d, d, with straight stem, and working in two
guides descending in the two mortices e, a; the action of the governor compels the
two mortices to move to and fro, actuating the tappets o, o¹, in a similar manner
each in its turn. f, f, rod actuated by the regulator 9, 9, carrying a counter-
weight , which is moved forward or backward to regulate the speed of the
engine. i, i, part of the uprights where the slide blocks are carried. j, j, forked
levers carrying sockets to receive the tappets. k, h, blocks secured between forks
and working in the guides i, i.