Apparatus for Indicating & Recording
Year: 1889

page_text: I THOMAS THORP of Whitefield in the County of Lancaster Engineer 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 Apparatus for Indicating & Recording the speed of
Machinery and the pressure of the Steam in the Boiler, (and is also applicable in
part to indicating and recording the pressure of other fluids) and its object is to
obtain thoroughly reliable indications and records.
According to my invention when used as a combined speed & pressure indicator
and recorder, both records are made at the same time and preferably on the same
paper vertically over each other clockwork being used to drive the drum on which
the diagram paper is placed.
In carrying out that portion of my invention relating to the indication of and
recording the speed of Machinery, I make use of a Tank partially filled with oil or
other suitable liquid; from the bottom of this tank and preferably on one side rises
a tube or leg to some considerable distance above the level of the liquid.
From the bottom of the tank also rises a small cylinder to about the level of the
liquid having communication with the tank through perforations preferably near its
lower end, the upper end being closed. A vertical shaft runs through it to the
bottom of the tank or thereabouts, carrying a small screw propeller working about
midway in a small cylinder and having a pinion at its upper end driven by a crown
or bevel wheel attached to a shaft extending through the side of the tank and actuated
by the machinery the speed of which it is required to indicate and record.
The small cylinder communicates with the interior of the leg by means of a pipe
near the opposite end to the holes, but below the level of the liquid, so that when
the screw propeller is rotated, the liquid is forced through the pipe into the leg, or
vice versa according to the direction of rotation of the screw propeller.
Within the leg is a float working in guides, fixed to the leg, but without friction ;
This float has a rod running through & rising vertically from it & passes through a
slot in the plate covering the tank which serves as a top guide, and carries at its
upper end a marking pen or pencil pressing lightly against the paper on the drum on
which the record is required to be taken. This drum is fitted vertically & is driven

page_text: by clockwork preferably fitted within it, the paper being marked previously from a
Standard and replaced from day to day. The pen is caused to press lightly against
the paper, by having either the float or rod rising from it slightly weighted on the
side nearest the drum.
In order that the speed recording pen may be set to the required position on the
paper when the apparatus is in action, a cock or its equivalent actuated by a milled
head from above the plate is fitted near the bottom of the leg in which the float works,
so that more or less liquid may be allowed to escape back into the tank and thereby
cause the float to assume different positions, with the same rate of speed, and enabling
it to be set to the required position on the previously marked scale by observing the
actual speed of the Machinery to which the apparatus is connected.
When the speed indicator and recorder portion above described is in action, the
liquid being forced into the leg according to the speed at which the screw propeller
is rotated, the float necessarily rises with it and as the height to which the liquid is
forced is found to vary in a definate ratio with the speed of rotation, the position of
the marking point on the paper after being once adjusted indicates the speed of the
actuating machinery & the diagram which is continually being made is a record of it.
The usual methods of indicating & recording steam and other similar pressures are
by means of closed bent and flattened metal tabes or flexible metal diaphragms, the
range of motion of the same being very limited thus necessitating links & levers in
order to render the motion available, and so importing a certain amount of friction
and consequent unreliability.
According to that portion of my invention relating to indicating and recording
boiler or other similar pressures I also make use of a closed bent flattened tube,
preferably circular, the extremities nearly approaching each other.
To one extremity is soldered the steam or other connection, the other being free
to move. To the inner side of the free extremity of the tube when placed uppermost,
and to the outer side of the fast extremity or connection are secured one end of
each of two short thin metal strips, or their equivalents, the other ends being secured
to a roller about midway between the two extremities of the bent tube. To the ends
of this roller which is preferably of rather greater length than the width of the bent
tube, the ends of a biturcated lever are secured, the other end of the lever, in the
case of a recorder, extending beyond the bent tube & carrying a piece of metal or
other suitable material curved to such a radius that a band secured and depending
from it moves in a vertical direction as the lever also moves..
The lower end of this band is attached to the lower end also of a rod passing
through a slot in the plate covering the tank, near its upper end which serves as its
top guide, and carries the marking pen at its upper end, weighted in such a manner
as to cause it to press very lightly against the paper on the drum.
When the pressure indicator & recorder as above described is in action the pressure
within the bent tube tends to draw apart the two ends and in doing so slightly
rotates the roller to which the ends of the strips or their equivalents are attached and
as the marking pen is in direct communication with this roller through the lever,
band, and carrying rod a greatly increased range of motion is obtained, without the
use of links or other contrivance whereby friction is imported, the apparatus
constructed according to the above description being practically frictionless..
Although I prefer to use the same paper for indicating and recording both speed
and pressure it is necessary to use different portions of it for each purpose, 1 however
use the same hour lines for each.
Where only a pressure indicator is required I preferably fit the bent tube roller &
thin metal strips or their equivalents into a circular casing in such a manner that a
pointer can be used in the ordinary way, but in this case a spiral spring or its
equivalent is necessary in order to bring the point to zero.
And in order that my invention may be fully understood and readily carried into
effect I will proceed to describe the accompanying sheet of drawings reference being
had to the figures and letters thereon marked, the same letters applying to similar
parts in all the figures.

page_text: Figs. 1 and 2 are sectional elevations through A A & B. respectively, fig. 3 an
elevation, fig. 4 a plan and fig. 5 a sectional plan through (. C.
Fig. 6 is an elevation with dial plate removed and fig. 7, a sectional elevation
through D of my invention when used as a pressure indicator only A is the tank
partially filled with oil or other suitable liquid B, from the bottom of the tank rises
the leg C. The small cylinder D also rises from the bottom of the tank, perforations a, a,
preferably near the bottom form a communication between the interior of the small
cylinder D and tank A.
The vertical shaft E carries the small screw propeller b, and the pinion C at its
upper end, driven by the crown wheel or its equivalent d attached to the shaft e
extending through the side of the tank A. fis the small pipe connecting the interior
of the small cylinder D and leg C.
F is the float in the leg C working in the guides g. g. h is the rod carrying the
speed recording pen or pencil i pressing lightly against the paper on the drum G
driven by clockwork preferably fitted in any convenient manner into its interior j ;
k is the cock with milled head k¹ for adjusting the height of the pen i.
H is the flattened bent tube, to one extremity of which is attached the steam
l,
connection 7, m, m, are the thin strips of metal or the equivalents attached to the
piece p, on which is the band q attached at its lower end to the rod carrying the
pressure recording pen or pencil s also pressing lightly against the paper on the
drum G.
In figs. 6 and 7, L is the case into which the bent tube, thin strips & roller are
fitted, is the spiral spring or its equivalent and u the pointer, shown in dotted
lines.
Having now particularly described and ascertained the nature of my invention
and in what manner the same is to be performed, I declare that what I claim is :-
1. In speed indicators and recorders, the float F working between the guides g. g.
in the leg C carrying the rod and recording pen or pencil i floating in oil or other
suitable liquid B and actuated by the small screw propeller b, in combination with
the driven drum G in the manner & for the purposes substantially as shown, and
herein described.
2. In speed indicators and recorders the cock K or its equivalent fitted near the
bottom of the leg C in the manner & for the purpose substantially as shown, and
herein described.
3. In pressure indicators and recorders the flattened bent tube H, short thin metal
strips m, m, or their equivalents, the roller n and bifurcated lever O carrying the
curved piece p with the band q, or its equivalent attached to & carrying the rod r
with recording pen or pencils or its equivalent in combination with the driven
drum G in the manner and for the purposes substantially as shown and herein
described.
4. In pressure indicators-the flattened bent tube H short thin metal strips m. m.
or their equivalents, roller n, spiral spring t or its equivalent and pointer u, in
combination with a marked dial plate in the manner & for the purposes substantially
as shown and herein described.
DL: 10th T. 1800