IMPROVEMENTS IN INDICATORS FOR STEAM ENGINES AND OTHER PRIME MOVERS
Year: 1879

page_text: LETTERS PATENT to Herbert John Haddan, of the Firm of Herbert and
Company, Solicitors of Patents, of 67, Strand, in the City of Westminster,
Civil Engineer, for the Invention of "IMPROVEMENTS IN INDICATORS FOR
STEAM ENGINES AND OTHER PRIME MOVERS." A communication from abroad
by George Hannibal Crosby, of the State of Massachusetts, United States
of America.
ealed the 9th March 1880, and dated the 7th October 1879.
PROVISIONAL SPECIFICATION left by the said Herbert John Haddan at
the Office of the Commissioners of Patents on the 7th October 1879.
HERBERT JOHN HADDAN, of the Firm of Herbert and Company, Solicitors of
Patents, of 67, Strand, in the City of Westminster, Civil Engineer." "IMPROVEMENTS
IN INDICATORS FOR STEAM ENGINES AND OTHER PRIME MOVERS." A communication
from abroad by George Hannibal Crosby, of the State of Massachusetts, United
States of America.
The Invention relates, first, to a new parallel motion or mode of transmitting the
motion of the indicator piston to the marking pencil, and consists in attaching to
the upper side of the base plate or arm which supports the indicator drum two
vibrating standards, connected at their upper ends with the ends of two symetrically
inclined levers connected with each other by a pin in the centre line between the two
standards, one of said levers being prolonged beyond the pin and carrying at its
end the marking pencil, while the other lever is directly connected with the upper
end of the piston rod by a pin at a point having the same distance from the said
centre line as the marking pencil, so as to impart to the latter the motion of the
piston, but on an increased scale. The Invention consists further in constructing
the piston cylinder and surrounding it with a jacket in such a manner that both
can expand freely, the cylinder extending through the base plate of the drum, and
having the jacket fastened to it at its lower part only, without any communication
of the cylinder-bore with the jacket. The axle of the drum is not directly attached
to the base plate, but to a flat lever pivoted to the latter, the same pivot serving
also as axis for a horizontal guide pulley, and as pivot for a bracket carrying two
small (vertical) guide pulleys. The flat lever is placed under the influence of a
spring, preferably applied in a groove of the base plate, and tending to remove
the said lever with the drum from the marker when not counteracted by the

page_text: pressure of the hand. The flat lever and the base plate are further provided with
a second pair of pivot holes placed diametrically opposite the first one, so that the
position of the lever may be reversed, and for limiting the motion of the drum
against the marker; the flat lever has two concentrically curved slots, and carries
at each end of the latter a horizontal stop screw, while the base plate is provided 5
with two (vertical) stop screws, one for each slot.
The tension of the helical spring which effects the return motion of the drum is
made adjustable by attaching its upper end to a collar, which may be turned on the
axle of the drum and fixed in the required position by a clamp screw, while the
lower end of the spring is attached to the bottom of the drum. The motion of the 1
drum may be obtained as usual from the cross head of the engine by means of a
cord carried over the guide pulleys and wound upon the lower part of the drum,
and the whole indicator may be constructed of metal.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Herbert John Haddan in the Great Seal Patent Office on
the 6th April 1880.
HERBERT JOHN HADDAN, of the Firm of Herbert and Company, Solicitors of
Patents, of 67, Strand, in the City of Westminster, Civil Engineer. "IMPROVEMENTS
IN INDICATORS FOR STEAM ENGINES AND OTHER PRIME MOVERS." A communication
from abroad by George Hannibal Crosby, of the State of Massachusetts, United
States of America.
The indicator is to register the degrees of steam pressure exerted on the piston
of an engine during its stroke, the Invention consisting in improvements on
indicators of the kind provided with rotary drums or cylinders for supporting and
revolving the sheet of paper while it may be in the act of being marked by the
marker when moved vertically by the piston of the indicator, or by mechanism
operated thereby. As indicators of the class mentioned are well known and in
common use, and as their mode of operation and the results attainable by such are
well understood by engineers or person skilled in steam engines it will not be
necessary to describe such. In the accompanying Drawings, which serve to illus-
trate the Invention, is Fig. 1, a top view; Fig. 2, a front elevation; Fig. 3, a
rear elevation; and Fig. 4 and 5, transverse and vertical sections of an indicator
containing the Invention.
The Invention consists, first, in the combination of the two vibratory standards
and two levers arranged and combined with each other, and with the indicator,
piston rod, and supporting arm, essentially in manner and to operate as set forth;
second, in the piston cylinder applied to move lengthwise in its sustaining arm or
plate, in combination with an encompassing chambered jacket fastened to such
cylinder and its lower part only, and having no connection or communication with
the bore of the cylinder, whereby steam can flow from such bore into the jacket or
chamber; third, in the combination of a movable lever for supporting the drum
with such drum and the arm, by which the cylinder and the marker parallel motion
are sustained; fourth, in the combination of an actuating spring and stationary
and adjustable stops with the lever sustaining the rotary drum, and with the arm
furnished with the cylinder and piston and the marking mochanism or parallel
motion as set forth; fifth, in the combination of an intermediate or auxiliary guide
wheel with the drum, and with an adjustable arm provided with other guide
wheels, and pivoted or applied so as to revolve about the first named or intermediate
guide wheel; sixth, in a helical spring and adjusting column, and a clamp screw or
nut, or both, arranged and combined with the reciprocating drum and its spindle,
substantially in manner as set forth; seventh, in the arm or support plate provided
with opposite pivotal holes, in combination with the drum supporting lever
arranged upon such arm or support plate, and having opposite pivotal boles, all
being substantially as and for the purpose described; eighth, in the arm provided
with the opposite pivotal holes and a stop screw and screw holes therefor, in
combination with the drum carrying lever furnished with opposite pivotal holes,
arcal slots, stop screws, and screw holes, all being substantially as set forth; ninth,
in the steam pressure indicator, the drum thereof provided with mechanisin for
moving it up to and away from the marker, in combination with the said marker,
adapted to move only in a straight or vertical line or arc. In the Drawings, A
denotes the steam cylinder, coupled in the usual way with a stop cock B and
provided with a piston C, whose rod a projects through the head b of the said
cylinder. Encircling the piston rod is a helical spring D for depressing the piston
within the cylinder, such spring being extended from the piston to the head of
cylinder. The cylinder goes up through a flat arm E without being directly
attached thereto. At is lower part, however, the cylinder is screwed into the lower
part c, c, of a cylindrical jacket F, between which and the cylinder and surrounding

page_text: the latter is a narrow space d, which, with the jacket, serves to prevent radiation
or loss of heat from the cylinder. The jacket at its upper part abuts against and is
projected down from the support plate or arm E. From the above it will be seen
that both the jacket and the cylinder can be expanded lengthwise by the heat of
the steam without one in so doing being interupted by the other. There are
extended up from the arm E two standards G, H, which, arranged with the piston
rod as represented, are so pivoted at their lower ends to the arm as to enable each
of them to move or vibrate toward and away from the other. To the standard H
and to the head of a piston rod a lever I is pivoted and arranged as shown.
Furthermore there is jointed to the standard G a lever K, the connection of the two
being at or near the outer end of the lever. The said lever K is also pivoted to the
lever 1. The distance between the axes of the outermost pivots of the lever I is
equal to that between the axes of the pivots connecting the lever K with the
standard G and the lever I. At its inner end the lever K is provided with a
marker socket or carrier e, the distance of whose centre or axis from the axis of the
pivotal connection of the levers I, K, is equal to the distance of the later axis from
the axis of the pivotal connection of the lever I and the piston rod head f. When
the piston rod may be in vertical movement, a marker or pencil a² in the holder e
will have imparted to it a corresponding but faster or greater motion. The peculiar
parallel motion for effecting the said movement of the marker has been found to
operate to excellent advantage, the lever I of it being directly connected with the
piston rod head by a joint, and not indirectly by a link, as in some other parallel
motions, wherein the piston rod moves rectilinearly, particularly in that of the well
known Richards steam engine indicator. Furthermore there is arranged on and
pivoted to the arm E a flat lever L, whose fulcrum is a headed screw g, which
passes down through a grooved guide wheel h, screws into and through the arm E,
and serves as a pivot for a rotary furcated arm M, furnished with two grooved
guide wheels i, i. A clamp nut k, screwed upon the lower part of the screw g,
serves to fix the arm M in any desirable position within the range of its motion
around the wheel h. Besides having the holes k, l, made in them for reception of
the pivot g, the lever L and the arm E have two other like holes k², l', made in
them at like distances from the axis of the reciprocating drum N. This drum turns
freely on a spindle m extending up from the lever L, and near its lower end is
provided with a groove n made entirely around it. To this groove there is fixed a
cord o, which after having been wound in such groove one or more times around
the drum, is led partially about wheel h, and thence between the guide wheels i, i;
such cord, when the indicator is in use, being attached to the piston cross head, or
some other proper moveable part of the steam engine. A helical spring p. encom-
passing the spindle m, is attached at its lower end to the hottom of the drum, and
at its upper to a rotary collar q, arranged to revolve on the spindle, and provided
with a clamp screw screwed into such collar and against the spindle. Besides
such clamp screw the collar rests on a sleeve s surrounding the spindle, and may be
furnished with a set nut t screwed on the upper part of the spindle and against the
collar. By means of the collar and either or both of its clamps the spring may be
taken up or wound, as occasion may require, for it to operate with the requisite
pressure on the drum to cause such drum to revolve backward to its normal position
after it may have been revolved the opposite way by the cord. Like other drums
of the kind, it and its supporting device should be provided with stops to insure
such position of the drum. There is applied to the drum in the usual way a tube O
for carrying on its outer surface a sheet of paper spread thereon, it being held in
place by springs u, u. Furthermore there are in the lever L (a horizontal section
of which is shown in Fig. 6) two arcal slots w, w¹, which are arranged transversely
in it and at equal distances from the axis of the drum. Each slot is provided with
two screw holes s', s', at its opposite ends, to receive a pair of stop screws x, x.
There is also in the arm E a screw hole z, immediately under cach arcal slot, such
being to receive another stop screw a¹. These stop screws are to gauge and limit
the movements of the drum relatively to the marker. A spring 6' suitably applied

page_text: to the arm E and the lever L serves to retract the lever or move it and the drum
away from the marker, such lever being moved the opposite way by an attendant
with his hand applied to the lever, or to a handle inserted in the hole near the free
end of the said lever. By having the arm and lever provided with the two sets of
holes k¹, l, k³, l', and the slots, stop screws, and screw holes, arranged as explained,
the lever at either end may be pivoted to the arm, and may also have the inter-
mediate guide wheel and the arm carrying the pair of guide wheels applied to the
pivot when arranged in either pair of the pivot holes. By such means the indicator
can be adapted for being applied to either head of a steam engine cylinder, and
thus often save the necessity of using a pair of indicators, or one to each cylinder
head, as is the case with indicators as usually made. With the parallel motion
herein before described the marker will be moved at a much more rapid rate than
the piston C.
CLAIMS.
1. The indicator parallel motion, substantially as described, consisting of the two
vibratory standards G, H, and the levers I, K, arranged and combined with each
other, and with the arm E and the piston head ƒ essentially in manner and to
operate as set forth.
2. The piston expansive cylinder A applied to move lengthwise in the arm E in
combination with the encompassing chambered jacket F fastened to such cylinder
at its lower part only, and having no connection with the bore of the cylinder,
whereby steam can flow from such bore into the jacket or its chamber d.
3. The combination of the movable lover L with the arm E and the drum pivoted
to the said lever, and provided with marking mechanism, arranged with it and to
operate the marker substantially as described.
4. The combination of the actuating spring b¹, and the stationary stop a², and
adjustable stops x, x, with the lever L sustaining the drum, and with the arm E
furnished with the cylinder and piston and marking mechanism, substantially as
described.
5. The combination of the intermediate guide wheel h with the drum N and its
carrying lever L, and with the adjustable arm M provided with the guide
wheels i, i, and pivoted so as to turn about the said intermediate guide wheel h, as
set forth.
6. The helical spring p, the adjusting collar q, and the clamp screw r or nut t, or
both, arranged and combined with the reciprocating drum N and its spindle m,
substantially in manner and to operate as described.
7. The arm E provided with the opposite pivotal holes l, l', in combination with
the lever L arranged therewith and with the drum N, and provided with opposite
pivotal holes k³, k, all being substantially as and for the purpose described.
8. The arm E provided with the opposite pivotal holes 1, 2, and the stop screw a¹
and screw holes therefor, in combination with the drum carrying lever L provided
with the opposite pivotal holes k', k, the arcal slots w, w³, and the stop screws x, x,
and their two sets of receiving holes a¹, all being arranged substantially as set
forth.
9. In the steam pressure indicator, the drum thereof provided with mechanism,
substantially as described, for moving it up to and away from the marker in
combination with the marker having mechanism to move it only in a straight line
or path, as set forth.
In witness whereof, I, the said Herbert John Haddan, have hereunto set
my
hand and seal, this Sixth day of April, A.D. 1880.