Improvements in Dynamometers.
Year: 1892

page_text: Date of Application, 12th Apr., 1892-Accepted, 14th May, 1892
COMPLETE SPECIFICATION.
Improvements in Dynamometers.
I, EDGAR JAMES WOOD of No. 243, Broadway in the City of New York in
the State of New York, United States of America, 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 :-
My invention relates to improvements in dynamometers in which a record-
receiving disc or strip is actuated independently of the power-transmitting and
power-applying mechanism, and a marker, subject to the varying relation of the
said power-transmitting and power-applying devices, is arranged to make the
record upon the disc or strip, of the amount of power expended.
In the accompanying drawings,
Figures 1 and 2 represent in side elevation and transverse central section, an
embodiment of my invention, in which the connection between the power-trans-
mitting and power-receiving devices is effected by a confined body of fluid, and
the pressure is transmitted from the body of fluid to the indicator arm, and the
record-receiving disc or strip is adapted to be carried by the power-applying or
power-transmitting device.
Figures 3 and 4 are similar views of an embodiment of my invention, in which
the record-receiving disc or strip is independent of the power-transmitting or
power-applying devices.
Figures 5 and 6 are similar views of an embodiment of my invention, in which
the indicator arm is under the mechanical control of the power-applying or power-
transmitting device, and the record-receiving disc or strip is independent of the
power-transmitting or power-applying devices: and,
Figures 7 and 8 are similar views of an embodiment of my invention, in which
the indicator arm is under the mechanical control of the power-applying or power-
transmitting device, and the record-receiving disc or strip is adapted to be carried
by the power-applying or power-transmitting device.
Referring to Figures 1 and 2, A represents a driving shaft for transmitting
power from a source of power, not shown, to any desired mechanism. B represents
a pulley loosely mounted upon the shaft and C and C¹ represent a pair of arms
keyed to rotate with the shaft, and connected with the pulley as follows:-
A pair of cylinders D, D¹ are secured to the pulley at points, preferably about
Pistons within the
diametrically opposite and facing in opposite directions.
cylinders have their piston rods d and d loosely connected with the arms C, C¹, so
that if power be applied to the pulley B, to rotate it in the direction of the arrow,
it will tend to force the piston rods d, d', and their pistons, into their respective
cylinders, and when the advance movement of the pistons is interrupted, the
shaft A will be forced to rotate, together with the pulley. If, on the other hand,
the shaft A be forced to rotate in the direction opposite that denoted by the arrow
in connection with the pulley, it will have the same effect upon the pistons, and,
when their advance is interupted, cause the pulley to rotate with the shaft.
It is intended to charge the cylinders D, D' with a fluid, preferably a liquid, and
to provide liquid conduits E and E¹ in connection with the interiors of the
cylinders, and leading thence toward the hub of the pulley, and there communi-
cating through a common branch pipe e in connection with a passage way e¹ within
the hub, the opposite end of said passage way being in communication, through a
pipe e, with a gauge F. The common branch pipe e is provided with a stop
cock e.
The gauge which I prefer to employ is of the well-known type, in which a
curved nine has a tendency to straighten under the pressure of the liquid therein.

page_text: and in the present instance I have connected the free end of such pipe by a link f
with an index hand f¹, pivotted at f, and carrying, in its free end, a marking
device f³ I further provide for supporting a disc G in position to engage the
marking device f³, and provide a clockwork H, of any well known or approved
form, for rotating the disc G for such a length of time as may be required.
I prefer that the marking device f³ be so located with respect to the disc, as to
vibrate transversely across the face of the disc from its centre towards its circum-
ference, and I provide the disc with any suitable indicating marks, to denote the
relative pressures to which the gauge has been subjected under the loads which the
driving shaft has been forced to carry.
The clockwork, disc, and indicating arm, in fact the entire registering device, as
shewn in Figure 1, is fixed to rotate with the pulley B.
In operation, the varying pressures upon the fluids within the cylinders will be
transmitted to the gauge, and thence to the indicator arm, causing its free end
to swing more or less away from its normal or zero position, and thus indicate
the load carried by the shaft with great sensitiveness.
For the purpose of limiting the movement of the pulley relative to the shaft, and
adjusting it in such relation, I provide set screws 1, 11, set in lugs i fixed to the
shaft, the free ends of said screws being adapted to engage the opposite sides of a
lug on the side of the pulley B.
In the form shewn in Figures 3 and 4, I have shewn the common branch pipe e,
connected with the collar K, fixed to the hub of the pulley B, and there is mounted
loosely upon the collar K a sleeve or loose collar L, having in its face, adjacent to
the fixed collar K, an annular groove l, in communication with the branch pipe e.
The loose collar or sleeve L is fitted liquid-tight to the fixed collar K, and, as a matter
of expediency, I prefer to provide the face of the fixed collar K with oblique-faced
flanges and at its edges, the latter being made removable for the purpose
of slipping the sleeve or loose collar I into position.
The registering device, similar to that already described, may in this instance
be fixed in space, and connected with the loose collar or sleeve by a pipe N in
communication with the annular groove 1, the pulley itself being permitted to
rotate freely within said collar.
As represented in Figures 5 and 6, the connections between the pulley B and the
shaft A consist of springs D A rock shaft O is carried by the pulley, and has
one of its arms connected by a link o with the arm C keyed to the shaft A.
Another arm o¹, carried by the rock shaft O, has a pin and slot connection with a
bar p fixed to a collar P, which has a sliding movement along the hub of the
pulley B. The exterior of the collar P is provided with a series of annular
teeth p', adapted to intermesh with the teeth of a spur wheel Q, mounted in a
suitable support independent of the pulley and its shaft.
A toothed sector is secured to rotate with the spur wheel Q, and said sector
engages a rack bar r on the stem of the indicator bar R, carrying the marker r'.
A record-receiving strip S is arranged to be unwound from one rollers and
wound on another rollers; the latter being actuated by ordinary clock-works.
A smooth faced table T is provided, over which the strip S is drawn beneath the
marker. The strip S, like the discs herein above referred to, may be sub-
divided to correspond with the varying amounts of power, and the marker will be
caused to travel across the face of the strip by the movement of the arm C
relative to the pulley B, such movement being communicated through the link o,
rock shaft O, bar p, sliding collar P, spur wheel Q, and sector g. At the same
time, the collar may rotate freely with the pulley, its movement along the shaft
being the only movement which affects the indicator.
In the embodiment of my invention shewn in Figures 7 and 8, the indicator
bar R¹ is pivotted to the arm C, one of its ends being connected by a link U with
the pulley B, and its opposite end carrying the marker. A spur wheel V is
mounted concentric with the pulley B, and is connected thereto by a coil spring v.
The disc to receive the record is carried on the face of the spur wheel V.

page_text: A clockwork W, secured to the pulley B, is geared to the spur wheel V, and
controls its movement, while the coil spring serves as the actuating spring for the
clockwork.
In both the forms represented in Figures 5, 6, 7 and 8, a dash pot w is employed,
to prevent sudden changes in the relative positions of the arm C and pulley B.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In combination, a power-transmitting device, a power-applying device having
a yielding connection with the power-transmitting device, a record receiving disc
or strip free to travel, an indicator arm adapted to be moved when the power-
transmitting and power-applying devices move relatively to each other, and means
for operating the record-receiving disc or strip independently of the power-
transmitting and power-applying devices, substantially as set forth.
2. In combination, a power-transmitting device, a power-applying device having
a yielding connection with the power-transmitting device, a record-receiving disc
or strip free to travel, and mounted on a support fixed relatively to the movements
of the power-transmitting and power-applying devices, an indicator arm adapted to
be moved when the power transmitting and power applying devices move relatively
to each other, and means for operating the record-receiving disc or strip inde-
pendently of the power-transmitting and power-applying devices, substantially as
set forth.
3. In combination, a power-transmitting device, a device for applying power to
the power-transmitting device, means for confining a body of fluid to form a
connection between the power-transmitting and power-applying devices, and an
indicator, under the control of said confined body of fluid, for indicating the
varying loads upon the power-transmitting device, substantially as set forth.
4. In combination, a power-transmitting shaft, a pulley loosely mounted on the
shaft, means for confining a body of fluid to form a connection between the
pulley and shaft, an indicator arm under the control of said body of fluid, and a
dial having a predetermined movement past the indicator arm, substantially as
set forth.
5. In combination, a power-transmitting shaft, a pulley loosely mounted on the
shaft, means for confining a body of fluid to form a connection between the
pulley and shaft, an indicating device held against movement with the pulley,
and a fluid connection between the indicating device and the said means for
confining a body of fluid, substantially as set forth.
Dated this 12th day of April 1892.
NEWTON & SON,
Agents for the Applicant.