Improvements in or relating to Valve-gear for Fluid-pressure Engines.
Year: 1895

page_text: Date of Application, 1st June, 1895*
Complete Specification Left, 7th Feb., 1896-Accepted, 11th Apr., 1896
PROVISIONAL SPECIFICATION.
Improvements in or relating to Valve-gear for Fluid-pressure
Engines.
A communication from ADRIEN PROLHAC, Junior, Merchant, of Allègre, in the
Republic of France:
I, ALFRED JULIUS BOULT, of 323 High Holborn, in the County of Middlesex,
Chartered Patent Agent, do hereby declare the nature of this invention to be as
follows:-
This invention relates to valve-gear for fluid-pressure engines.
run
The ordinary reversing gear of steam engines cannot be employed to work in
combination with continuous rotary valve-gear. My correspondent has therefore
devised, to enable such rotary valves to be used on engines which are to
reversely a special mechanism which is the subject of the present Application.
Continuous rotary valve-gear provided with its characteristic internal devices
and not constituting the main feature of the present invention is mounted on the
main cylinder of the engine in such manner as to permit also the mounting on the
same cylinder, above the ports of its ordinary steam passages, of a cylindrical box
or case pierced through its lower side with two openings, arranged so as to
communicate and correspond accurately.with the aforesaid passages of the steam-
cylinder. The case is provided with a central partition which divides it into two
similar circular chambers and is prolonged downward to divide each port into two
equal parts.
On the inside wall of the case, the aforesaid openings are separated by a solid
bar whereof the width in the present example is exactly equal to that of each of
the said passages.
The compartments of the case correspond each to one end of each of the two
said passages. The compartments are closed at their outer ends by covers, and at
the upper sides communicate with pipes or passages, which latter communicate
with corresponding parts of the similar compartments of the distributing valve
casing by pipes.
the
In each compartment of the box are arranged circular discs, mounted, so as to
be capable of rotating therein with slight friction and keyed on spindles, of which
spindles the outer ends project through the covers, while their other ends, facing
each other in the centre are journalled in the central partition of the case;
said discs are respectively provided on their lower sides with flanges turned towards
the centre partition and of such circumferential length that, during the angular
movement of the said discs, the ends of such flanges never travel so far as to
uncover at any one time the two parts of either of the ports, the two parts being
here understood to mean the halves of the opening, which are the one on one side
and the other on the opposite side of the partition in the wall of the case, against
which wall these flanges are adjusted to move with gentle friction.
t
The flanges are each pierced, in the middle of their length with a port of a
breadth which, in the present instance is equal to that of the aforesaid passages
and of the intermediate solid bar, in combination with which these ports work.
Thus arranged the ports of the flanges (equal in length and width to the said
passages of the case) have each-taking into consideration that the passages are

page_text: 1
i
separated by the width of the dividing partition-a length less than half that of
the ports of the steam cylinder; i.e. that, by moving the discs through a small
angle, the said steam-ports can each be put in communication, at will, with either one
or the other of the compartments of the case; i.e. either port with one compartment
and the other port with the other compartment.
For the purpose of producing such angular oscillating movements, to and fro, of
the discs, the free extremity of the spindle on one disc, outside the case carries,
secured to it, the socket of a lever arm whereof the downward end is jointed to a
horizontal longitudinal rod, prolonged forward to the part where the manoeuvre is
effected, and backward. (towards the cylinder end) so as to be jointed at this.rear
point to another lever-arm, having its upper end secured to a countershaft held
and rotating in bearings and used for operating the other disc.
At its opposite end (towards the other side of the apparatus) this countershaft
carries, keyed upon it, a toothed sector, arranged to gear with a similar toothed
sector, of equal diameter and pitch, keyed outside the case and on the outer end of
the spindle of the said other, disc.
From these arrangements of rod, levers and toothed sectors for manipulating the
discs, it follows that the discs will simultaneously rotate over equal distances, but
in opposite directions to each other, in the compartments of the case; and that,
for each of the extreme positions of the longitudinal rod-the oue forward, the
other backward-the discs will assume one of their two corresponding opposite
positions.
For the extreme position, forwards, of the rod, the angular movement of one
disc, in one compartment, will have taken place say from front to rear, and the
said disc, having reached its extreme position in that direction, its port will
exactly coincide with that part of the passage opening into the same compartment
of the case; on the other hand, and simultaneously, the angular movement of the
other disc, in the other compartment, will have taken place in the opposite direction
to the preceding, i.e. from rear to front, and, in the extreme position of this latter
disc on its port will exactly coincide with the part of the passage opening into the
same compartment of the case.
From the foregoing it follows that, for the extreme rearward position of the rod,
the angular movements of the discs, will take place simultaneously in contrary
directions the one to the other, but inversely to the preceding case.
It results therefore from these arrangements that, for a given position of the
crank-say, for instance, the upper-position, for a locomotive-the position of the
organs will correspond to the movement of the piston to the right the steam
conducted by the admission pipe being, at this moment distributed from the com-
partment of the rotary distributing valve, to pass by passages to act upon the rear
face of the piston.
During this admission of the live steam to the rear face of the piston, the
exhaust steam, having previously acted upon the opposite face of the piston,
escapes by other passages to the exhaust side of the rotary distributing valve.
The same position of the crank being assumed, for consideration, to produce the
back stroke of the motor it will suffice to place the aforesaid rod in its furthest
position backwards, i.e. to the left, which will have, as its result, as previously
explained, to place the discs in the case in their other extreme positions which will
thus realise, as will easily be understood, the reversal, as compared with what has
preceded it, of the direction of the steam and exhaust, and consequent working of
the engine..
The reversal of the course of the steam being thus brought about, the steam
distribution will naturally continue its usual course.
Dated this 1st day of June 1895
BOULT & WADE,
Agents for the Applicant.

page_text: Improvements in or relating to Valve-gear for Fluid-pressure.
Engines.
A communication from ADRIEN PROLHAC, Junior, of Allégre, in the Republic
of France, Merchant.
I ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
Chartered Patent Agent 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 relates to valve-gear for fluid-pressure engines.
The ordinary reversing gear of steam engines cannot be employed to work in
combination with continuous rotary valve-gear of the kind described in the
Specification appended to my correspondent's Application No. 10456 of 189; for
Letters Patent. I have therefore devised, to enable such rotary valves to be
used on engines which are to run reversely a special mechanism which is the
subject of the present Application, and is illustrated in the accompanying drawings,
wherein.
Figure 1 represents a vertical longitudinal section of the steam cylinder of an
engine to which is applied this new reversing-gear in combination with continuous
rotary valve-gear.
Fig. 2 is a general plan of the entire arrangement shown in Fig. 1 ;
Fig. 3 is a partial cross section on the line X-Y of Fig. 1.
Fig. 4 is a cross section and end view on line X-Y₁ of Fig. 1; and
Figs. 5 and 6 are sectional plans of a detail of Figs. 1 and 4 hereinafter
particularly referred to.
The continuous rotary valve-gear A described in the said Specification appended
to the Application No. 10907 of 1895 provided with its characteristic internal
devices and not constituting the main feature of the present invention is mounted
on the steam cylinder B in such manuer as to permit also the mounting on the same
cylinder, above the ports C C' of its passages D D', of a cylindrical box or case E
pierced through its lower side with two ports F F arranged so as to communicate
and correspond accurately with those D D₁ of the steam cylinder B but each
divided into two equal parts. The case E is provided with a central partition H
which divides it into two similar circular chambers II and is prolonged downward
to divide each port F F¹.
On the inside wall of the case E, the ports F F' are separated by a solid bar G
whereof the width. in the present example is exactly equal to that of each of
the said ports F F'.
The compartments I I¹ of the case E, correspond each to one end of each of the
two ports FF. The compartments are closed at their outer ends by covers J J¹,
and at the upper sides communicate with the pipes or passages K K respectively
which latter communicate with the corresponding parts L L of the similar
compartments M M' of the distributing valve casing A by the pipes N_N..
In each compartment II of the box E are arranged circular discs P P', mounted,
so as to be capable of rotating therein with slight friction and keyed on spindles ✪ ✪¹
respectively of which spindles the outer ends project through the covers J J, while
their other ends, facing each other in the centre are jouroalled in the central
partition H; the said discs are respectively provided on their lower sides with
flanges QQ turned toward the central partition H and of such circumferential
length that, during the angular movement of the said discs P P', the ends of such
flanges never travel so far as to uncover at any one time the two parts of either of
the ports F, the two parts being here understood to mean the halves of the opening,

page_text: which are the one on one side and the other on the opposite side of the partition H
in the wall of the box E, against which wall these flanges Q Q¹ are adjusted to
move with gentle friction.
The flanges QQ are each pierced, in the middle of their length with a port S
and S respectively, of a breadth a which in the present instance is equal to
that of the ports F F and of the intermediate solid bar G, in combination
with which these ports work.
X
Thus arranged the ports S and S₁ of the flanges QQ (equal in length and width
to the ports F F of the box E) have each-taking into consideration that F F are
separated by the width of the dividing partition G (or H)-a length y less than
balf that of the ports C C¹ of the steam cylinder B; i.e. that, by moving the
discs P P through a small angle, the said steam ports C C' can each be put in
communication, at will, with either one or the other of the compartment I or the
compartment I' of the box E, i.e. either port with one compartment and the other
port with the other compartment.
For the purpose of producing such angular oscillating movements, to and fro,
of the discs P P', the free extremity of the spindle O' of one disc P₁, outside the
box E, carries, secured to it the socket of a lever arm T whereof the downward
end is jointed at T¹ to a horizontal longitudinal rod U (Figs. 2 and 4), prolonged
forward (towards the crank-shaft) at U to the part where the manœuvre is
effected, and backward (towards the cylinder end) at U so as to be jointed at
this point to another lever-arm V, having its upper end secured to a counter-
shaft V held and rotating in bearings and used for operating the other disc P.
At its opposite end (towards the other side of the apparatus) this countershaft V₁
carries, keyed upon it, a toothed sector V arranged to gear with a similar toothed
sector, of equal diameter and pitch with the sector W, keyed outside the box E
and on the outer end of the spindle O of the disc P.
From these arrangements of rod, levers and toothed sectors for manipulating
the discs, it follows that the discs will simultaneously rotate over equal distances,
but in opposite directions to each other, in the compartments I I¹ of the box E;
and that, for each of the extreme positions of the longitudinal rod U-the one
forward, the other backward-the discs P P' will assume one of their two
corresponding opposite positions, as shown respectively in Figs. 5 and 6.
For the extreme position, forwards, of the rod U represented in Figs. 1, 2 and 4,
the angular movement of the disc P, in compartment 1, will have taken place from
front to rear-i.e. from left to right of Figs. 1 or 2, and the said disc, having
reached its extreme position in that direction, its port S will exactly coincide with
that part of the port Fopening into the same compartment I of the box E; on
the other hand, and simultaneously, the angular movement of the disc P¹, in the
compartment I', will have taken place in the opposite direction to the preceding,
i.e. from rear to front, or from right to left, and, in the extreme position of the
disc on this side, its port S¹ will exactly coincide with the part of the port F1
opening into the same compartment of the box E; these two extreme positions
of the discs P P¹ for the extreme forward position of the longitudinal lever. U
are clearly shown in Fig. 5.
From the foregoing it follows that, for the extreme rearward position of the
rod U, the angular movements of the discs P P₁, will take place simultaneously in
contrary directions the one to the other, but inversely to the preceding case, i.e. that
the one disc P will have turned from left to right and brought its port into exact
coincidence with the part of the port F1 opening out into compartment I; while
the disc P will have turned from right to left, and brought its port S' into exact
coincidence with the part of the port F opening into the compartment 1'; these
two extreme positions of P and P-opposite to what previously occurred
and corresponding to the extreme rearward position of lever V are. clearly
represented in Fig. 6.
It results therefore from these arrangements that, for a given position of the
crank say, for instance, the upper position, for a lo 'omotive,—the position of the

page_text: organs as shown in Figs. 1, 2, 3, 4 and 5 will correspond to the movement of
the piston to the right the steam conducted by the admission pipe A¹ being, at
this moment, distributed from the compartment M of the distributing valve, thus :
to pass by the passages L, pipe N, passage K, compartment I of box E port S an 1
disc P, corresponding and coincident part of port F in box E, and lastly to enter
into the steam cylinder B by the port C and passage D and act upon the rear face
of the piston W
During this admission of the live steam to the rear of the piston, the exhaust
steam, having previously acted upon the opposite face of the piston, escapes by
other passages D', port C', corresponding part of port F of box E corresponding
port S of disc P, compartiment 1' of the distributing valve A and exhaust pipe Ai
of the distributor (or valve box) A.
The same position of the crank being assumed, for consideration, to produce
the back stroke of the motor it will suffice to place the aforesaid rod U in its
furthest position backwards, i.e. to the left of Fig. 1 which will have, as its result,
as previously explained, to place the discs P P in the box in the position shown
in Fig. 6 which will thus realise, as will easily be understood, the reversal, as
compared with what has preceded it, of the direction of the steam and exhaust, and
consequent working of the engine.
The reversal of the course of the steam being thus brought about, the steam-
distribution will naturally continue its usual course, i.e. the compartment M M' of
the distribution-valve A, and the corresponding compartments 1 1 of the box E,
realising in succession, by their mutual combination and that of their internal
organs, the admission and subsequent exhaust of the steam to and from each
piston face.
Having now particularly described and ascertained the nature of this inven-
tion as communicated to me by my foreign correspondent I declare that what I
claim is ;-
1. A reversing-apparatus for fluid-pressure engines consisting of the combination
with a distribution-device such as A in which a rotary valve is employed of a
valve-casing such as E having a central partition dividing it into two chambers
and having its wall in each chamber perforated with a set of ports to connect each
of the said chambers with both ends of the engine cylinder and also perforated
with two passages one at each side of the partition each individually appropriated
to one of the tubes communicating with the device A a valve such as P or P¹
in each said chamber to control the said set of ports therein and means for
operatively connecting the said valves reversely with each other and with an
cperating-rod substantially as and for the purpose described.
2. A reversing-apparatus for fluid-pressure engines consisting of the combination
with a distribution-device such as A in which a rotary valve is employed of a valve-
casing such as E having a central partition dividing it into two chambers and
having its walls in each chamber perforated with a set of ports to connect each of
the said chainbers with both ends of the engine cylinder and also perforated with
two passages one at each side of the partition each individually appropriated to one
of the tubes communicating with the device A a disc with a perforated flange on a
spindle in each chamber to control the said set of ports therein, toothed sectors on
these spindles operatively connected with each other and with an operating-rod
substantially as set forth.
3. The combination and arrangement of parts constituting a complete reversing-
apparatus for fluid-pressure engines substantially as and for the purpose described
and illustrated in the accompanying drawings.
Dated this 7th day of February 1896
BOULT & WADE,
Agents for the Applicant.