IMPROVEMENTS IN ENGINE POWER METERS
Year: 1882

page_text: LETTERS PATENT to Charles Vernon Boys of Wing near Oakham in the
County of Rutland for an Invention of "IMPROVEMENTS IN ENGINE POWER
METERS
"
PROVISIONAL SPECIFICATION left by the said Charles Vernon Boys at
the Office of the Commissioners of Patents on the 19th July 1882.
CHARLES VERNON BOYS of Wing near Oakham in the County of Rutland
"IMPROVEMENTS IN ENGINE POWER METERS
"
For this
In the Specification to Letters Patent granted to me on the 3rd June 1881,
No 2449 I described a form of integrating apparatus for measuring engine power
in which a cylinder reciprocating longitudinally in time with the strokes of the
piston has pressed against its surface a disc which is swivelled to a more or less
oblique attitude by an arm worked by flexible diaphragms subject to the steam
pressure, the cylinder being thereby caused to turn more or less round always in
one direction, so that the amount of its revolution is a measure of the engine
power. My present invention relates to an improved construction of apparatus of
this kind, the object which I have in view being to separate the more delicate
part of the instrument from the parts in which the steam acts and to render the
instrument more conveniently applicable to engines of various kinds.
purpose I employ a small vertical cylinder like that of an ordinary indicator but
communicating at its two ends with the two ends of the engine cylinder, and I fit
this indicator cylinder with a piston having its rod extended upwards and attached
to an adjustable helical spring which is compressed or extended according as there
is excess of pressure below or above the indicator piston.
cylinder and separated from it by an open framing I fix a closed box containing
Above the indicator
the integrating apparatus. As the piston rod passes through this box to the
spring above, in order to prevent steam or moisture from being blown into the box
fix on the piston rod below the box an inverted cup collar which deflects down-
vards auy jet from the cylinder below. I make this collar of rectangular or
olygonal shape or provide it with projecting arms so that it can be engaged by a
ocket or stops on the bottom of the box when the piston rod is drawn upwards,
nd the piston rod can thus be prevented from turning when the spring is screwed
[Price 6d1

page_text: or unscrewed. Usually in working, the piston turns more or less round; 1
therefore instead of connecting it directly to the arm which swivels the integrating
disc, fit on it between collars a bracket which works up and down in a rectilineal
For moving
guide and which has a pin working the arm of the swivelling disc.
the integrating cylinder to and fro I provide a slide which is guided rectilineally
along a bar fixed in the box and which has arins embracing between them the
two ends of the cylinder. This slide is moved to and fro by a lever, worked from
some part of the main engine moving in time with the piston, or it may be moved
by a rack and pinion the pinion being moved by gearing from a reciprocating
In both cases as a cord forms the most
pulley worked from the engine.
convenient connection to the engine, I employ a spring to effect the backstroke.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Charles Vernon Boys in the Great Seal Patent Office on the
17th January 1883.
CHARLES VERNON BOYS of Wing near Oakham, in the county of Rutland 1
"IMPROVEMENTS IN ENGINE POWER METERS
"
For this
In the Specification to Letters Patent granted to me on the 3rd June 1881
No: 2449, I described a forin of integrating apparatus for measuring engine power,
in which a cylinder reciprocating longitudinally in time with the strokes of the
piston has pressed against its surface a disc which is swivelled to a more or less
oblique attitude by an arm worked by flexible diaphragms, subject to the steam
pressure, the cylinder being thereby caused to turn more or less round always in
one direction, so that the amount of its revolution is a measure of the engine
power. My present invention relates to an improved construction of apparatus of
this kind, the object which I have in view being to separate the more delicate part
of the instrument from the parts in which the steam acts and to render the
instrument more conveniently applicable to engines of various kinds.
purpose, I employ a small vertical cylinder like that of an ordinary indicator but
capable of communicating at its two ends with the two ends of the engine cylinder,
and I fit this indicator cylinder with a piston having its rod attached to a helical
spring which is compressed or extended according as there is excess of pressure
below or above the indicator piston. Above the indicator cylinder and separated
from it by an open framing, I fix a closed box containing the integrating apparatus.
As the piston rod passes through the bottom of this box, in order to prevent steain
or moisture from being blown into the box, I fix on the piston rod below the box
an inverted cup collar which deflects downwards any jet from the cylinder
upwards. This collar may be made of rectangular or polygonal shape or provided
with projecting arms so that it can be engaged by a socket or stops on the bottom
of the box, when the piston rod is drawn upwards and the piston rod can thus be

page_text: prevented from turning when the spring is screwed or unscrewed.
working, the piston turns more or less round; I therefore, instead of connecting it
Usually in
directly to the arm which swivels the integrating disc, connect it thereto by a
swivel. For moving the integrating cylinder to and fro I provide a slide which is
guided rectilineally along a bar fixed in the box and which has arms embracing
between them the two ends of the cylinder.
rod, cord or strap worked from some part of the main engine moving in time
This slide is moved to and fro by a
with the piston, or it may be moved by a rack and pinion, the pinion being moved
by gearing from a reciprocating pulley worked from the engine. In both cases as
a cord or strap forms the most convenient connexion to the engine, I employ a
spring to effect the back stroke.
Fig: 1 of the accompanying drawings is a transverse section and Fig: 2 is a
side elevation partly in longitudinal section of one form of engine power meter
according to this invention; Fig: 3 being a plan of the integrating part of the
apparatus. A is a small cylinder like that of an indicator having its upper and
lower ends connected by unions to branch pipes B, leading to the two ends of the
engine cylinder, so that the piston C fitted in A is always subject to the same
difference of pressure on its two sides as the piston of the engine cylinder. I prefer
to make the cylinder A with a lining a in the part where the piston works with a
space between it and the exterior so as to diminish the liability of the interior of
the cylinder being injured by a blow on its exterior.
it a spring D suited both for extension and compression, and as this spring is
The piston C has attached to
exposed to damp, I prefer to gild it.. The piston rod passes up through a hole in a
plate E which forms the bottom of a semi-cylindrical box containing the integrating
mechanism. This box is supported on an open bracket casting E³ which is fitted
to the top of the cylinder A with a swivel joint at e held by a clamping nut. By
loosening the nut at e, the box can be turned round to any desired attitude and can
be secured in that attitude by tightening the nut. A collar d fixed on the piston
rod prevents any fluid that may escape from the cylinder around the piston rod
from being spurted up into the box above.
a swivel F which is linked to a sleeve f that is. fitted to slide along an arm g
On the top of the piston rod is fitted
projecting from the swivelling frame of the integrating disc G.
means of a spring g' bearing against the end of the axis of its swivelling frame is
This disc by
pressed against the surface of the integrating cylinder H. The cylinder H is fitted
to slide along its axis which, being fitted to H with a feather or with a square or
polygonal section, must turn with H and communicate the revolution of H to the
gearing of a counter which is accommodated within a cylindrical casing I provided
with a glass front i through which the indices of the counter can be seen.
two ends of the cylinder H are embraced between the arms of a frame K which is
The
fitted to slide along a rod . It is pulled in the one direction by a flexible steel
strap L connected to a part of the engine moving proportionally to and in time
with the piston, and it is retracted by a spring 7.
shewn by dotted lines in fig: 3) on the side of the frame K, rack teeth gearing with
In some cases I provide (as
pinion m having on its axis a pulley M from which a strap or cord L' extends
to the moving part of the engine. It is convenient to fix on the rod k two pieces
of split tube le grasping & with a certain amount of friction; as the frame K is
moved to and fro, it pushes these pieces along the rod and they remain in the
extreme position to which they are pushed, so that a measurement taken between
hem can determine the stroke of K. The action of the apparatus is like that of
he apparatus described in ny previous specification above referred to, No: 2449 of
he year 1881, that is to say-As the piston C subject to the varying pressure in
he engine cylinder is moved up and down in opposition to the spring D, its rod
cting on the arm g, causes the disc G to take attitudes more or less inclined to the
xis of the cylinder H, which is moving to and fro. By the frictional contact of G
nd H the cylinder H is, during its to and fro motion, caused to turn more or less
ound, according as the plane of G is more or less inclined to the axis of H, and the
mount of its revolution registered by the counter in I (to which the axis of H is

page_text: geared) is a measure of a quantity proportional to the power of the engine, that is
to say, it measures the product of the varying pressures acting on C multiplied by
the spaces moved over by H. As the change of pressure on C at the beginning of
each stroke of the engine piston corresponds with the change of direction of the
two and fro motion of H, it follows that H is caused by the obliquity of G always
to turn in the same direction.
The apparatus may be somewhat modified in form as shewn by the part
vertical section fig. 4 in which the bracket framing E¹ is made in form of
a cone with lateral openings and the spring P is accommodated within the
Another modified form
cone, and not within the cylinder A as in Fig. 1.
is shewn by the part transverse section Fig 5, the longitudinal section fig 6,
and the plan fig: 7. In this case, the spring D is accommodated above the
integrating mechanism and the arm g of the swivel frame of the integrating disc
has a slotted hole engaging a pin f which projects from a plate c, attached to the
piston rod and fitted to work in a guide c¹.
The collar which prevents spurting of fluid past it being made square or
polygonal or with projecting arms, and a socket or studs e¹ being provided on the
plate E, the collar d', may be engaged with e¹ as with a spanner preventing it and
the piston rod (on which it is fixed) from turning when the nut which holds the
spring D is turned. The other parts of the mechanism corresponding with those
shewn in figs. 1, 2 and 3 are marked with similar letters.
In any of the forms of meter above described a card may be fixed on the
reciprocating frame K and a pencil or tracer may be attached to the piston rod so
as to trace on the reciprocating card a diagram which will correspond with an
ordinary indicator diagram.
Having thus described the nature of my invention and in what inanner the
same is to be performed, I hereby declare that I make no general claim to
measuring engine power by arranging a disc having its plane more or less inclined
in accord with the steam pressure to bear against and turn more or less a
cylinder moved to and fro in time with the engine piston and geared to a counter,
but I claim -
First-The construction of engine power meter, substantially as herein described
with reference to figs 1, 2 and 3
Second-The modified construction described with reference to fig. 4
Third: The modified construction described with reference to figs. 5, 6 and 7.
In Witness whereof, I the said Charles Vernon Boys have hereunto set
my hand and seal this seventeenth day of January, in the year of our
Lord, one thousand eight hundred and eighty-three.
C: V. BOYS. (L.S.)