IMPROVEMENTS IN ROTARY ENGINES, ROTARY PUMPS, AND OTHER LIKE APPARATUS
Year: 1878

page_text: LETTERS PATENT to Alexandre Vacherot, of Clyde House, Bridge Road,
Battersea, in the County of Surrey, for the Invention of "IMPROVEMENTS IN
ROTARY ENGINES, ROTARY PUMPS, AND OTHER LIKE APPARATUS."
Sealed the 26th November 1878, and dated the 7th June 1878.
PROVISIONAL SPECIFICATION left by the said Alexandre Vacherot at
the Office of the Commissioners of Patents on the 7th June 1878.
ALEXANDRE VACHEROT, of Clyde House, Bridge Road, Battersea, in the County
of Surrey.
"IMPROVEMENTS IN ROTARY ENGINES, ROTARY PUMPS, AND OTHER
LIKE APPARATUS,”
My Invention relates to that description of rotary engine pump or like
apparatus, in respect of which Letters Patent were granted to me, dated November
3rd, 1875, No. 3828, and it consists,-
First. In operating the sliding valves or pistons described in the Specification to
the said former Letters Patent, in order to move them into and out of contact with
the stationary boss within the revolving cylinder by means of stationary cams in
lieu of by steam or other motive fluid as described in the said former Specification.
The cams may be formed by a groove in the frame in which works rollers connected
to the pistons or valves.
2ndly. In the use of two radial stops or partitions carried by the boss, one of
which is or may be perforated so as whilst allowing the steam to pass through it
in order to operate upon the piston or valve beyond it to provide sufficient area to
form an effective resistance or abutment for the back pressure of the steam. By
this arrangement the advantage is obtained of what is known as compounding"
in engines, in which the exhaust steam is conducted from one cylinder into another
of larger capacity so as to render available to the utmost the motive power of the
steam
"

page_text: It is preferred to employ a valve provided with suitable annular or semi-
annular grooves and passages so arranged that by the act of turning it from one
position to another the steam pipe may be placed in communication with the
port which has been serving as the exhaust port in the cylinder, and the exhaust
pipe placed into communication with the port which has been previously used as
the steam port in the cylinder, and the direction of motion of the engine reversed
accordingly.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Alexandre Vacherot in the Great Seal Patent Office on the 27th
November 1878.
ALEXANDRE VACHEROT, of Clyde House, Bridge Road, Battersea, in the County
of Surrey. "IMPROVEMENTS IN ROTARY ENGINES, ROTARY PUMPS, AND OTHER
LIKE APPARATUS.”
""
My said Invention relates to that description of rotary engine pump or like
apparatus, in respect of which Letters Patent were granted to me, dated November
Third, One thousand eight hundred and seventy-five, No. 3828, and it consists,—
First. In operating the sliding valves or pistons described in the Specification to
the said former Letters Patent in order to move them into and out of contact
with the stationary boss within the revolving cylinder by means of stationary cams
in lieu of by steam or other motive fluid, as described in the said former Specifica-
tion. The cams may be formed by a groove in the frame in which works rollers or
sliding pieces connected to the pistons or valves.
Secondly. In the use of two radial stops or partitions carried by the boss, one of
which is or may be perforated so as whilst allowing the steam to pass through it in
.order to operate upon the piston or valve beyond it to provide sufficient area_to
form an effective resistance or abutment for the back pressure of the steam. By
this arrangement the advantage is obtained of what is known as "compounding
in engines, to which the exhaust steam is conducted from one cylinder into another
of larger capacity so as to render available to the utmost the motive power of the
steam.
31
By using also two solid stops and providing two inlets and two outlets for the
motive fluid two engines are obtained in one.
The valve employed may be provided with suitable annular or semi-annular
grooves and passages so arranged that by the act of turning it from one position
to another the steam pipe may be placed into communication with the port which
has been serving as the exhaust port in the cylinder, and the exhaust pipe placed
into communication with the port which has been previously used as the steam
port in the cylinder, and the direction of motion of the engine reversed accordingly.
And in order that my said Invention may be fully understood, I shall now

page_text: proceed more particularly to describe the same, and for that purpose shall refer to
the several Figures on the annexed Sheet of Drawings, the same letters of reference
indicating corresponding parts in all the Figures.
Figure 1 of my Drawings represents a front sectional elevation of an engine
constructed according to my said Invention (the section being taken along the line
1, 2, in Figure 2). Figure 2 is a vertical section of the same taken at right angles
to Figure 1.
Figure 3 is a rear elevation.
Figure 4 is a detail of a portion of the internal framing shewing the passages for
the motive fluid (the view being taken from the rear side).
Figures 5, 6, and 7 are details of the distributing valve, Figures 5 and 6 being
elevations of the front and rear sides respectively, and Figure 7 a horizontal
section taken along the line 3, 4, Figure 6.
A is the shaft of the engine, which is supported in bearings at a, a, in the
standard B and fixed frame B', and may be fitted with driving pulleys or other
gear for transmitting motion or power. On this shaft I key the piece C, which,
with the piece C₁ attached thereto, forms what I designate the cylinder, the same
having formed therein slots or guideways for the reception of valves or pistons
D, D, D, D³, which are capable of sliding towards and from the centre of the
engine; the said slots or guideways are fitted with stuffing boxes at 6 in order to
render the interior of the apparatus fluid tight. In the interior of the cylinder
C, C¹, I arrange the stationary boss E, which is attached to a piece F, in its turn
bolted to the frame B¹, and also having attached to it another piece G; the several
parts E, F, G, B¹, and B, forming together the framing of the engine. The boss E
and the cylinder C, C', are so arranged relatively the one to the other that a
space or chamber H is left between the external periphery of the boss and the
internal periphery of the cylinder with the exception of at two points, at which
the boss is fitted with radial projections or stops I, I', the outer extremity of which
fit the bore of the cylinder C, C', against which they may be pressed by a spring or
otherwise, if desired. The pistons D, D', D2, D3, are also normally in contact with
the external periphery of the boss, and their sides form the piston surface, against
which the steam (for example) acts when admitted to the chamber H, through the
port c, as herein-after explained. Rotary motion is thus imparted to the cylinder
C, C', in the direction denoted by the arrow, the steam acting upon the piston D
(which, for example, may be assumed to be then in closer proximity to the port c
than is indicated in the Drawing), whilst the stationary partition I forms the neces-
sary resistance or abutment. As the cylinder C, C¹, rotates the pistons D¹ and D³
will be brought into proximity to the stops I', I, respectively, and it will bo
necessary to retract the said pistons in order to allow them to pass the stops. This
is effected by means of a cam groove K formed in the parts F, G, of the framing, in
which groove rollers d, d, provided on the pistons, work the cam, being made
of such a shape as to cause the pistons to be retracted, so as to enable them
to pass the stops, and then moved into contact with the boss E at the
requisite periods, In the position shewn in the Drawings the pistons D¹, D³,
are represented as having been retracted, and in the act of passing the stops I¹, I,
respectively. By the time the piston D arrives in proximity to the stop I¹ the
piston D³ will have passed the steam port c, and the steam will act upon the said
piston. As also the piston D is retracted in order to enable it to pass the stop I¹
the steam, which has been imprisoned between the two pistons D³ and D, will
escape past the piston D, and pass through an aperture e, formed in the stop I'
The steam is thus expanded, and acts upon the piston D', the solid portion of the
stop providing a sufficient area to form an effective abatement or resistance. The
piston D is then again moved into contact with the boss, and in its turn receives
the steam which has passed through the aperture e, in the stop T, after escaping
past the piston D³. A similar action takes place with all the pistons in suc-
cession, whereby the rotary motion of the cylinder is maintained with a minimum
expenditure of steam, the advantages of expansion and compounding being secured

page_text: by the use of the perforated stop I', which admits of the steam expanding into a
larger capacity as in the compound engine of the well-known construction. The
exhaust steam finally escapes at c¹.
The pistons are provided with grooves, as shown at 6', by full lines in Figure 1,
and by dotted lines in Figure 2, for the reception of packing of any suitable
description to render the joints fluid-tight, or grooves may be provided in the
cylinder in lieu of in the piston if preferred. The cylinder is also provided with
grooves, as shewn at 62, in Figure 2, for the reception of packing for a like
purpose.
The packing may be so arranged as to be easily regulated by screws if desired.
In order to enable the motion of the engine to be readily reversed I employ a
valve L (shewn in detail in Figures 5, 6, and 7) in the cover M (forming a portion
of the frame B¹) and around the shaft A, so as to admit of the shaft turning
freely therein. This valve is provided on its rear side with two semi-annular
grooves f, g, to the former of which (f) steam is supplied through an opening at
h, in the cover M; the steam is then conducted through an aperture i (see Figures
6 and 7), and thence through a passage k, in the piece F, shewn most clearly in
Figure 4, to the steam port c. The exhaust steam is conducted from the port c
along the passage in the piece F, into the annular groove m on the inner side of
the valve L, thence through an aperture n into the semi-annular groove g, from
which it escapes through an opening o in the cover M into the atmosphere or
elsewhere, as required.
When it is required to reverse the engine the valve is turned upon its axis by
means of the handle N, with which it is provided from the position indicated by the
dotted line p to that denoted by the dotted line q, in Figure 3, whereby the passage
k is brought into communication with the annular groove m, leading to the exhaust
outlet o, and the passage is brought into communication with the aperture i*,
leading from the steam inlet h, and the engine is accordingly reversed.
In Figure 3 I have represented the handle in an intermediate position for the
facility of shewing the different passages and openings. By placing the handle in
this position, the engine will be stopped, also by varying its position between the
two extreme points, the ports may be more or less opened, as required.
In lieu of employing the reversing distributing valve herein-before described, any
equivalent valve cock or cocks may be used, the same being arranged to be worked
by a handle or otherwise, or each of the ports may be fitted with a three-way cock
so as to admit of the motion of the engine being reserved by changing the position
of the cocks, and thus using the steam port as the exhaust port, and vice versa; or
when a capability of reserving is not required a single distributing valve may be
employed, such, for example, as that described in my said former Specification.
The ports and distributing valve, or valves, or cocks may also be so arranged that
the steam shall be only admitted during a portion of each fraction of a revolution
corresponding to the distance tetween two of the pistons of the cylinder in order to
utilize to the utmost the expansive action of the steam; the said valve, or valves,
or cocks may be also so arranged as to regulate the speed of the engine.
The apparatus may be used as a pump by driving the shaft by means of any
suitable prime mover, in lieu of the same being actuated by the agency of fluid
admitted into the cylinder, as before mentioned, or two engines may be mounted
on the same shaft, the one serving as the motor and the other as the pump.
In a similar manner the apparatus may be utilized as a blower will be well
understood.
When the apparatus is used as a pump or engine, if two stops are employed, they
both may be unperforated, and an inlet and an outlet may be provided at opposite
sides of each of the stops, thus forming a double pump or double engine, as the
case may be.
Having now described and particularly ascertained the nature of my said In-
vention, and the manner in which the same is or may be used or carried into

page_text: effect, I will observe in conclusion that what I consider to be novel and original,
and thereform claim as the Invention secured to me by the herein-before in part
recited Letters Patent is,-
First. In a rotary engine, rotary pump, or other like apparatus of the description
herein-before referred to, operating the sliding valves or pistons by means of
stationary cams, substantially as and for the purpose herein-before described.
Second. In a rotary engine, rotary pump, or other like apparatus of the des-
cription therein-before referred to, the employment of two radial stops or
partitions carried by the stationary boss, one of which is either perforated or
not, substantially as and for the purposes herein-before described.
Third. The general construction, arrangement, and combination of parts,
substantially as herein-before described, and illustrated by my Drawings.
In witness whereof, I, the said Alexandre Vacherot, have to this my Speci-
fication set my hand and seal, the Twenty-seventh day of November,
One thousand eight hundred and seventy-eight.